Help with compact cranks....

I have the FSA on my Orbea and the Shimano on my tri bike Kuota K factor.

I don't feel a difference...does color matter? Both match other components better on each bike.

You'll love a compact..not at Bassman but for sure if you end up doing IMLP in '09. 

Be sure you get the right crank arm length for you. 

It is based mostly on how tall you are. Also you could measure what size you have now.

If I recall right you are a few inches taller than I am. I'd look at the bike specs of the bike you currently have in your size for a guide.

I'm pretty sure mine are 170 but I'm 5'5.5" 

FYI,  if you see a crank with a 48 big ring (like the Centaur 48/34) it is a Cylocross crank, not a regular compact crank for roadies.    Not that it wouldn't work, you just might run out of gear occastionally.  

FOr crank lenght, check the original specs to see what it came with.  It should also be stamped somewhere on the crank arm, usually someplace you can't see easily unless you go looking for it.   Generally it is 170 or 175, but if you are short it might be 165.   Match the crank arm length when you buy a new crank, or you could have fit/geometry issues. 

The only other thing to look for is the Bottom Bracket.  You'll probably need a new BB to match the new crank.  Anymore, the BB is designed for a specific crank, so read the specs for the crank to see which one you need.  You may also need a special tool or two to install the crank.  (BB tool and/or crank puller)

One other thing the might be considered is the rear cassette.  If you are changing your gearing to compact, you may want to get a wider range in the rear.  Maybe go with an 11t small cog to get more speed out of the new 50t, or a 27t big cog to help even more with climbs.  Not required, it would just be a good time to do it.    It is probably a good time for a new chain as well. 

This looked like a good deal on a nice crank:

http://www.pricepoint.com/detail/15927-100_TRUEL7-3-Parts-56-Cranks/Bolts/Truvativ-Elita-2.2-Road-Crankset-'07.htm

FWIW, my bike came with Campy and an FSA Gossamer (53/39).  The ISIS bottom bracket got wrecked pretty quick.  But a new bb worked fine and after switching to an FSA mega-exo compact, I have had zero problems.  Didn't even need to change the FD.  No compatability issues for me.

Check out the one from pricepoint I linked above.  It inlcudes a new BB as well.   Should be a pretty nice setup and about the same component level as what came on the s32.   I think you'll prob want a 172.5 on the crank length, but get the same length as what came on the bike. 

For arguement sake if you currently have a 53-39 with a 12-25 cassette and go to a 50-34 with a 11-23 cassette you top speeds at 90rpms will be:

53-12  31.1
39-25  11.0

 50-11 32
34-23 10.4

As you can see you really don't gain much is ease by going to the compact.  I think there are really others reason for going to compacts but I have no idea what they are.