I just stick a bit of busted flip flop down the front of my wetsuit. No cost and no-one can see it. A tiny bit of extra flushing on the chest though so if its really cold where you are diving it might not work too well.
As for hardening up, it doesn't seem to be getting any easier for me if I forget my flip flop once in a while. Especially now that I'm using a 1.4m railgun with single 20mm band and only a single notch. Also, I think my body tries to stop me hurting myself and I have a really hard time loading without some chest protection - I just can't pull hard enough.
Yeah, I thought about something like that but figured it might move around with enough activity. Water is pretty warm here so flushing is not too big a problem, but loose things moving around ARE a problem. I think I'll probably try gluing a thin chest pad for a little protection, and then allow myself to toughen up as per Pastor's suggestion. Don't want to disappoint the reverend :t
Will see what Armand's setup is like first though.