I know this thread is 2 yrs old, but for anyone interested in a Trek 470 ... go for it.
It's a nice quality steel bike, wasn't top of the line, but well made sturdy and rides nice.
Two things to look out for are the rear spacing which is a tad less than modern bikes being 7 speed, and the brifters. The RSX Shimano brake-shift lever combos often stop working, usually because they stiffen up, either from dirt, grit, dried oil, whatever. The accepted solution is to flood them with wd40 (something you wouldn't normally use on a bike) or maybe t-9.
Seriously, the brifters not working is one fo the biggest objection i've seen to these.
Well, the rear dropouts can be respaced by any competant and half awake bike mechanic, and the brifters are easy to fix if they will fix at all (if they are totally shot just take some bar end shifters and use those with a mornal set of aero levers)
I got one of these given to me and it only took an hour fo fiddling to get the recalcitrant shifter to function again (altho mine was more complicated, had to take the front part off and reseat an out fo wack washer). Yeh, unlike later shimano brifters these can sometimes be partially disassembled.
Also not for nothing but the frame is a prime candidate to build up with traditional downtube shifters.