I use a Lamy 1.1 in my joy and cp1.
But I write on WIDE ruled paper in normal Palmer cursive.
On college ruled paper, the ink line of the 1.1 nib looks messy because of the smaller line spacing.
What I am saying is the 1.1 nib needs a certain amount of space to write, and look good.
For reference I use an old US Parker F nib on college ruled paper and old US Parker M nib on wide ruled paper. I find the M nib too wide for use on college ruled paper.
I use everything from XF up to the 1.1 nib, all depending on how much space I have to write in; line spacing and box size on forms.
As for normal use, if you are taking about taking notes in school, I would rather use a F or XF nib. Simply because you can write denser and get more notes written on a line and thus more on a page. Also the F or XF will use less ink than the 1.1, so your ink load will last longer.