I'm about to pull the trigger on an Allez Comp Cr-Mo, but am a little hestitant on the sizing. Basically I was comparing geometry between 58cm specialized allez, trek 2300's, and cannondale r800. The allez has a 582mm eff TT, while the others are 172-175mm eff TT. Does the compact geometry of the allez play a role in this? Are the Allez really longer in real life? The Allez Comp Cr-Mo comes in a 57 and a 58, the 57 has a 172mm TT.

I'm a newbie when it comes to road bikes and fit. Also, I've been mtn biking for 3yrs or so now. I test rode a 56 allez an da 58 allez, the 56 seemed alright and the 58 seemed a little long (but again remember I used to riding a mtn bike in a non aero position). I'd kinda like to go w/ the 58 b/c it has a bit wider bars, and 175 cranks instead of 172.5 (so my spin doesn't have the change between road a mtn). I had ALOT of seatpost exposed on the 56 to get proper leg extension, and the sales guy slide the seat back a little, and flipped the steem so it had 15+ rise. He said I could fit on either the 56 or 58. He didn't mention the 57 size and I didn't see it until later on the internet. I'm not sure if specialized offers it built up or just a frame, but it's on the website listing crank leght and h-bar width, etc..

Is shortening a stem 10mm a big deal to handling to get the fit right? Or would it be better to get a 10mm longer stem? Or get the 57 which falls inbetween and there'd be less adjustment, but shorter cranks than my mt bike?

Thanks for any and all help.

Well, my shop called up specialized and they didn't have or know of 57cm Allez frames. Not sure what's up w/ that, but the shop owner and both sales guys agreed that the 58 would fit me great. So I went ahead and ordered an 04 Allez Comp Cr-Mo 58cm, supposedly there were only 2 04's in 58cm left around, 05's MSRP went up $$ w/ no change to the specs it looked like.