Thanks for all the replies! To clarify, I don't really care too much about the tan lines. I've almost always had a farmer's tan which I can now call my runner's tan. The few times I've run shirtless, I've noticed the sweat under my arms and along my torso where my arms brush and I can see how I'd possibly get some chafing there if I didn't protect those areas. If I run in shirts all the time but then switch to a singlet, I imagine I'd have some of those same issues or maybe different ones popping up.
So, does everyone run in shirts then switch to singlets for the races? I tend to burn pretty easily, so I figure 2 hours or so in the sun running a Half in a singlet may result in some sunburn.
I totally agree with the need to be serious about the sport. I wear tech t-shirts, good socks and shorts, as well as properly fitted shoes. I also wear doorags to protect my bald head. For the last couple of races (10k and a 5k), I've worn my somewhat funny Sesame Street cotton t-shirts. I don't know if I'd wear them for a Half, but they were fine for these races. I'm not fast enough to be worried about showing someone up. My running is for me, but one day I dream of winning my AG in some race somewhere...anywhere.
If I'm going to run in a singlet, and taking advice from here to not wear anything you haven't worn before, I figure I'd need to wear the singlet on some long runs. The FRB singlet is just one of the cotton ones, so I don't know if I'd wear that for a race unless I'd worn it a few times on long runs and didn't have an issue with chafing. I'm not fast enough to wear (or get) one of the tech FRB singlets, so do I just stick with the tech shirts?
April - I should start another post on the shirtless. How toned do your pecs and 6-pack have to be to run shirtless?
I've never been one that's been toned enough to want to show my bod off. I have run shirtless a few times from my work gym, but since we have to have a shirt on in the gym, I just strip it off outside, tuck it in the back of my shorts and I'm off. Since I sweat a ton, I need the shirt to wipe the eyes and forehead occasionally once my doorag gets saturated. So, I don't know that I'd be able to run completely sans shirt unless I had wristbands on to wipe the sweat.
Honestly, everyone, I don't care what I look like when I run. I run for fun and for my fitness, not to show off my killer tan or awesome muscles or coordinated outfits. I just thought it was an interesting question to ask and get some feedback on.