after i got an Amoresy catsuit, i couldn't go back to leggings of any kind, the feeling of having your whole body covered was literally 50% more satisfying than just having your lower body in spandex (at least for me anyway)
so my personal suggestion would be to forget about leggings altogether and only go for body suits
the rationale simply being, the more coverage the more satisfying
i actually threw away my entire collection of leggings/tights after i wore the Amoresy catsuit because i knew i wouldn't be going back to leggings
it's like toast vs toast + butter, after you've tried toast + butter, you'll never go back to simply eating a piece of toast on its own
well, that's my opinion and preference anyway
as for which suit, if you can reach one arm over your shoulder, and the other arm under, and make your finger tips touch behind your back, then i believe you can work the back zipper
if not, then yes, the front zipper would be more fitting
so the Athena suit for back zipper, or Celestia for front zipper
regarding size, there are two points on your body that can stress the zipper as you put the suit on
#1 hips
#2 shoulders
if you think you have wider hips and/or shoulders than average for a man of your height, then i'd suggest ordering one size larger than the suit recommended based on their height chart (others have even recommended buying 2 sizes larger)
if you have narrow hips and/or shoulders, then i think following their chart recommendation is fine
i made the mistake of ordering one size smaller, and honestly, it feels like the zipper might break every time i put the suit on
the main point of concern is shoulder width, imo that has little to do with body fat %, and more to do with bone structure
this is the height/weight range recommendation per size for the Celestia suit:
M Fit for height 150-165cm ,weight 40-60KG
L Fit for height 160-170cm ,weight50-65KG
XL Fit for height 165-175cm ,weight 60-80KG
2XL Fit for height 170-185cm ,weight 75-90KG
3XL Fit for height 180-190cm ,weight 85-100KG
so you're 5'11 at 240 pounds - that converts to roughly 180cm at 109kg
based on that data, i' think the 3XL might be the safest bet
You have to remember that the Celestia is a woman's suit. I'm 177cm and 73kg and for me XXL is the perfect fit. It's tight, but allow some movement and have room for my dick to stretch the fabric.
My first suit was an XL, and it was very hard to even put it on, I was just able to pull it over my shoulders . . .
My chest is 35 inches, my waist 35 and my hips 39.