Road Cycling - Crank question

I'm building a Surly Cross Check that will be used as a road/touring/commuter (sometimes XC) bike. I'm spec'ing it out and have a question regarding cranks. I'm familiar with MTB brands and levels (ie, Race Face v. XT, XTR, etc) but am unfamiliar with road cranksets. I know that I want a splined bb, and double chainring on a durable crankset that can be used on and off road. I was initially thinking Ultrega but noticed that the Campangnolo Centaur and Veloce are comparably priced. I always thought the Campagnolo stuff was top of the line, pricy stuff. Can anyone advise as to a good, reasonably priced (not Dura Ace) crankset that will be appropriate for my kind of riding? Also, what about shifters and derrailleurs? As always, any advice will be appreciated.

Campy still uses square taper BBs on its cranks, but it is a different length taper than Shimano, et al. Ultegra is more than you need. If you are going to build a triple, why don't you just stay with the MTB stuff you are more familiar with? Other than using a larger big ring, there isn't really any difference.

I have a 105 crankset on my Poprad. No problems whatsoever on either the road or dirt. For hardcore CX, I'll change it out for a Coda 38/29 and a different chain.

55/Rad

Do you need any particular length ?
What cog combos. Campy limit you to a 39 inner, and Shimano is a 38. There are some smaller bolt circle (110m) cranks that can go down to 34. Being non-Shimano, they use an ISIS spline.

i'm running an FSA (http://shop.store.yahoo.com/cyclocrossworld/fsagocrcr.html) gossamer (http://store.airbomb.com/ba/asp/ic.CR4126/ab/Itemdesc.htm) 'cross crank (http://www.roadbikereview.com/Cranksets/Full%20Speed%20Ahead,Gossamer,Cyclocross,Crankset/PRD_102928_2491crx.aspx#reviews) with 48/38 rings and a 13-25 cassette. this setup works really well for general road riding, and i'd imagine that it'd work well for anything else i'd ever want to throw at it. the cranks are pretty stiff, and i believe they were cheaper than 105 cranks when i got them last year.

I think that if weight is an issue, road cranks tend to be lighter. MTB cranks are mostly 175 in lenght. Depending on your leg lenght, and riding style, a shorter cranks could be better. I was riding 172.5 for years and have decided to experiment with 170s. The shorter length allows for smoother (and faster) spining on the flats. I went with lower gears and I think I can spin faster going up a hill. Now, if only more companies offer cross cranks with a 110 bcd.

Try looking into the Truvativ Elita Cyclocross crankset. Among the best choices for stiffness with its ISIS bottom bracket.