Rhodia paper -- I use it two-sided with no bleed through (Rhodia Dotpad No 16, ~$6). Rhodia and Clairefontaine paper can generally be used both-sided with no issues. There's a Japanese brand, Profolio that I also like, and 2-sided is not an issue. The best paper I've ever written on is the Rhodia No 18 premium. It's $16 per pad (A4 sized) but the glide is smooth and the quality is amazing.
I'm currently partial to the Leuchtturm 1917 master series, at least in part because of all the beautiful colors there are to choose.
https://www.jetpens.com/blog/the-best-fountain-pen-paper/pt/...
Currently using a Waterman fountain pen, but also have a Lamy safari nearby. Still don't know which one I like best.
For me the best part of using fountain pens is that I enjoy writing and taking notes more than with a regular pen. Also, my handwritting looks easier to read with the fountain pen.
Just my 2c.
A - what ink do you use? I'm still looking for one that works really well. Main thing is I hate blead through the paper B - Do you use the Rhodia paper one sided or two sided? I'm looking for a paper that I can use two sided with no bleed through, but other than super thick sketch paper haven't found anything.