I have a Pelikan 200 and I've used the M, OBB, OM and Italic nibs with it. My use of these nibs has included Pelikan ink (but too long ago to remember exact details) and they only have been used with Noodler's Squeteague, Noodler's Lexington Gray, Noodlers Navaho Turquoise, or Swisher's Cocoa recently.
I also have a Sailor music nib

, and that is a good reference nib for me to compare the B, OBB, OM and Italic nibs.
First, the issue of possible toothiness in a Pelikan nib. My impression is that Pelikan nibs are pretty much flawless. Any toothiness is more likely my fault, or the fault of using less than optimal paper. Toothiness happens sometimes it's related more to my not holding the pen properly, rather than any defect in the nib itself.
So, the my impression on on anything other than buttery smooth action from the nibs, is this. All of my Pelikan nibs are a little toothy if I use too much pressure, or if I'm using really cheap paper. Sometimes I've had the nibs pickup a bit of lint or dust into the nib, sort of getting it stuck between the tines, and that just requires a wipe off with a damp cotton ball or a peek under a magnifying glass and removal of the offending fiber. (I knit a lot and fibers floating around are a fact of life for me.)
Other problems that I experience with Pelikan broader nibs, such as the OBB and OM occur when I am not holding with the "sweet spot" working best, or if I am pressing down even a little bit. That goes almost double for the OBB nib. The OBB nib demands a very light touch between pen and paper. Think floating along on the top of the paper. Some days it almost feels like I am writing in the air above the paper, but still the ink hits the page and letters appear.
The OM nib acts pretty much like the OBB nib in terms of requiring a very light touch between the pen and the paper and needing to find the sweet spot. The OM nib doesn't have as much ink flow, so in that respect, it is a better nib for writing for me if I'm having a "smallish writing" day.

It also gives a nice line variation if I, the user, am doing what I ought when writing with it.
I had a Mont Blanc Noblesse fitted with a OB nib, and that had the same response as I recall. Of course, that was in my callow and carefree youth. Think back to the time when dinosaurs were roaming what became the Great Plains, so the memory is a bit hazy on that point.

My conclusion is that the OM lays down a line that is about equal to my other B nibs, but with subtle line variation. The OM is also close to other M nibs I've used, especially if I'm using an ink with super wet flow properties, on humid days or somewhat cheap paper that might not feather, but just seems to draw a huge amount of ink from the nib.
As Richard Binder says, Pelikan obliques don't give a lot of line variation. I just can't remember where on his site he said it, and my 'puter doesn't like me much today. I agree with him, except the subtle variations are there with an OBB, OB or even an OM nib. None give as much variation as you see with the Pelikan Italic or the Sailor music nibs.
As the Pelikan nibs lay down a lot of ink, relatively speaking, my writing size has to enlarge a bit for legability. The OBB requires the largest writing, then the Sailor Music nib. The Pelikan Italic is a virtual tie with the Sailor music in terms of ink flow and line width, but the difference with the Sailor is that the line variation is more subtle and more beautiful to me.
Next in line for requiring larger writing to get the any available variation from the Pelikans is the OM. then my Mont Blanc B (tied with a Waterman

, and so on down the size scale to EF.
With some inks, the OM can be just a bit broader than the Montblanc B or Waterman B nibs. However, the difference is really minimal. The OM is usually a thicker line writer than a Waterman B, but gives more line variation.
The italic nib feels balky or toothy only when I'm writing on my ultra-ultra-ultra- cheap (err, inexpensive) 20# copier paper. Even if i am using a 24# paper, making sure of course to be on the front, or "top side" of the paper, the nib can feel "toothy".
Check the paper label for which side should be loaded to make the top the printed side in the printer, and that's the top, or better side, for writing. On HP paper, the top is the side of the paper that is NOT on the seam side of the paper covering the ream. Put another way, the bottom/second side, or rougher side is close to the seam of the paper covering the ream of HP all purpose paper.
My guess is that if the Sailor music nib is broad for you, and the Pelikan B is not broad enough, you may find that the OM will be a good choice, but the OBB will be the really broadest line. You can, (but only with a small amount of practice in my experience), get line variation from the OBB, or OM nibs, without the feedback of a difference in your hand as you achieve the variation that the Sailor music nib gives. In other words, you can get line variation, but not quite as obvious as the Sailor. The feedback from the pen is not as obvious from the Pelikan broader nibs, no matter what.
My Pelikan italic nib gives crisp line variation no matter what, and also gives great feedback to my hand while doing so.
The problem I have with any of these nibs is that I sometimes need about a half page of writing to get my hand acclimated to the "lighter--as in no pressure" action. Also, the practice writing is required to get the best response from the nibs. If you're only using one or two pens all the time*, you probably won't have to practice much after you learn the variations that are possible with those nibs.
A conversation, if you were the proverbial fly on the wall, might go like this:
"Lighter pressure. "write, write, write--
"No, LIGHTER pressure."write, write write---
"No, no no no no--FLOAT along as you write. LIGHTER STILL. Are you an idiot hand? THIS REQUIRES a REALLY light touch..."write, write, write...
"You need to FLOAT along, not press even one bit. These are Pelikan nibs, they are smooth and you need a REALLY LIGHT TOUCH."write, write, write...
And so it sould go, if only my pens could audibly talk, or shout, at me. The quotes are what my pens would say. They do a bit of shouting, especially if I've just used a reluctant fine nib or had a nib react badly to some paper. If I've just used a ballpoint, well my pressure on the Pelikan is disastrous, whatever nib I'm using.
I know this is an absurdly long post, but I had fun writing it, and actually I'm using this for a rough draft on a violinist repair manual. (That's right, violinist repair.) You just got about 80 percent of a chapter on "training your hand--with a fountain pen" related to light pressure lessons to help injured violinists recover the proper touch on the bow or fingerboard as they recuperate. I left off the bowing and fingering exercises, figuring you wouldn't be using a Pelikan fountain pen to crank out a violin concerto any time soon.

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* Yeah, like
that would happen any time soon for FPN Twelve Step Participants!