I recently purchased a used Giant FCR 3 that was converted to drop bars. The guy decided to leave the 09' Altus RD paired with Shimano 600 STI shifters and a compact 105 crankset. Wouldn't it have made more sense to upgrade to Sora/Tiagra/105? The shifters are $200 on eBay which could have converted the cost of something more modern and reliable. It shifted fine when I took it for a test ride but now it's acting up. Fortunately I was able to snag it at a fantastic price (yeah, that's probably why) so a replacement shouldn't be a problem and the whole package would still leave me ahead.

The new 9-speed Claris group doesn't look too bad for a commuter bike. Sora is only marginally cheaper than Tiagra and 105, but Claris shifters are half the price. And the F&RD are less than $35 a piece. Do I save the cash and go Claris? Should I fork over a little more for something better? Or should I just work with what I have and just replace the chain and cassette?

I obviously won't be racing/touring or doing long distance riding or hill climbing.