Seriously, I thought I never would. I refused to be one of those guys who wears spandex because I thought everyone who did wore them just because they caused less aerodynamic drag than regular clothes which I thought was silly since I'm not trying to win races or anything.
Well I started doing longer rides. My butt was not happy, and when my butt isn't happy the rest of me isn't happy either. I was constantly shifting around in the seat trying to relieve various pressures or chafing and as a result my lower back and hands hurt from taking the weight off my butt. After as little as 17 miles today (admittedly after a longer 21 mile ride yesterday, also uncomfortable) I was miserable. I could get out of the saddle for a few minutes and be okay but the butt would be complaining again after a mile or two.
Even then I still wasn't willing to admit that I needed cycling shorts, but I finally went out and bought a cheap pair of Canari 6 panel shorts from Academy Sports...20 bucks...
Even right now my butt hurts and hates me if I sit in the saddle with my regular gym shorts...but earlier today riding with my spandex was something else. Even with my butt being horribly abused the 6 mile ride I took wasn't bad at all. I didn't shift in the seat except to relieve pressure on my sit bones occasionally (which, by the way, was the ONLY place I felt pressure) and when I got home, aside from the tired leg muscles I didn't even know I'd taken a ride.
And as a result of my weight loss, I'm able to fit into the medium size (30-32 inch waist) and I don't mind the way my legs look in them...actually think they look pretty good...that's a new first for me.
I'm not getting the spandex top to match, but despite being dead set against spandex from the start...I'm a believer. If your butt is giving you issues and you haven't already, give the cycling shorts a try. They really do help, even the cheap pair I got.