1. Overall design 5*
If Mont Blanc is Rolls Royce, Krone Fashion pens (not the LE's) are Lamborghini, OMAS is Ferrari, Pelikan is BMW, then the place reserved for Conway Stewart is surely Jaguar. Each company expresses its design philosophy in a unique way, and for Conway Stewart, the essense of CS is "refinement, with a bold element". With Jaguar, everything is refinement, but the single bold element is the line fo the car. With CS, the lines are classic, and the bold element is the variety and selection of striking celluloid resins. From Nebula
to Meteor
, Heather
, Coral Green
, Flecked Amythyst
and the Whirls,

these are not sedate resins.[color samples courtesy of Richardspens.com]
The 100 is an enlarged version of the 58 which as far as I can tell dates back to the 50's and has not changed in styling whatsoever. From its Vacumatic-style jewel and clip, to the triple cap band, torpedo shape, flat section face, and stepped cap profile this is a classic pen in every sense of the word.

I actually ordered the resin version that was for me most sedate, "Peppered White". What I expected was White resin chunks, with black chunks interspersed. What I got was a pleasant surprise. The white is a wonderful milky translusence, and the "black" is really pearlescent midnight blue. For those of you who know my penchant for blue pens, this turned what I thought woudl be a great resin into something spectacular. Because the blue is so dark, the pearlesence shows through only at some angles, and at others the midnight blue is flat and borders on black. In addition, there are hints of black interspersed within the white resin making for a great marbling effect. So what I thought would be a sedate resin has turned into a bold but refined one!
2. Size / Weight 4*
The resin is definitely celluloid and carries the familiar celluloid odor. It makes for a very lightweight pen. The pen is quite large, close to my Legacy 2 in size, but much lighter. This is comfortable pen in the hand, and even for its size would be comfortable for the long haul sessions.
3. Nib 4*

Nothing fancy. All function, and what great function it is. The pen is a fine, but lays down a big, juicy, smooth medium line. Single tone gold, even down to the iridium tip, with the classic Conway logo as its only ornament. Smooth as slick and well machined, and for the money I would expect it to be.
4. Filling Mechanism 5*

I generally have fickle relationships with filling mechanisms. I hate convertors for their, well, boringness, but like the fact that I can use the pen with a partially extended piston. I love pistons for the capacity, and elegance, but hate that most will not allow you to write with them in anything but the fully retracted position. I love sacs for their simplicity, but don't care for the weeping from thermal expansion and pressure changes. I think I have finally decided on the filling system that has the best of all worlds, and it is the one I ordered with the Conway. The CS has an piston system, but whose nob is hidden under the blind cap. It is actually an embedded convertor so the body of the pen is not the resovoir. Capacity, simplicity and the ability to extend the piston partially, this is the one. This pen and one of my Krone's share this system and frankly it is my favorite, and farely rare.
5. Fit / Finish 5*
Here Conway excels, and there is no doubt about it. I think next to my Nakaya, this is the best F/F pen I have. Some examples of the attention to detail.
a. Resin finish is magnificent, rivalling the smoothness of my Nakaya urushi.
b. Pen is engraved on the barrel in a "vintage" tradition, and the engraving is top notch. Pens like Conklin try this element, but I find the engraving to be cheap.
c. The translucense is used wonderfully. For instance, there is no inner cap. Instead a machined lip mates with the pens section face. What this allows for though is a ghostly nib profile to show through the cap. The translucense is also used to show the piston knob in the same fashion. The embedded convertor however, doesn't dirty the color fo the pen by allowing off color ink to show through the barrel. Just really stupendous!
d. Finally the nib is machined wonderfully.

6. Overall value 3*
At $330 (that's Pam Braun's price, retail is more like $375), this is not a high mark in the value category. You have to be a style maven to justify the price I think, but if you are this is a wonderful and beautiful pen.!