I have a GTB as a daily thrasher and it certainly keeps you awake because you WILL feel everything in the road
I thought the only advantage alu had over steel was in weight savings, and it just isn't the case here (5 lbs. with fork for a 62, same or more as the IRO)
however it does get lots of compliments from the general unknowing public
thick-ass tubeset = hopeful sturdiness
but I guess that's for the next owner to find out, since mine will be up for grabs at a tradeshow on the 17th
for reasons three: 1)I'll most likely recoup and then some, 2) the top tube is wangnormous and my lower back's had enough, 3) **** aluminum
p.s. I think a lot of the comfort issues would be sorted out with a carbon fork, but good luck finding one that's 1" threaded.