I ended up going with a 20" Tactical Solutions heavy barrel and a hogue black stock. Hopefully the extra weight won't throw the balance off too bad. I guess I'll just have to wait and see since I have already ordered it!No disadvantages to the 20" version in terms of function, reliability, or accuracy, but on a lightweight 10/22...every extra inch of heavy bull barrel you hang on the end of it is MUCH more weight to the overall rifle and obviously more forward weight that throws the balance of the rifle off IMHO. I stuck to the 18" barrel on all but one of the 10/22's I have built except for a 16 1/4" Volquartsen that my Dad wanted on his rifle. In terms of accuracy, his 16 1/4" volquartsen barreled rifle will keep up with my Shilen 18" barreled rifle out to 100 yards (don't know past that, but you are getting to the end of the rope on a .22lr much past 100 anyway).
The Green Mountain recommended above is a good barrel. I have seen lots of shooters built with the GM barrels. Shilen, Volquartsen, and Tactical Solution (TacSol) are excellent options!
TacSol won't weigh a thing compared to a solid steel (CM or Stainless) barrel like the Shilen or Volq. The TacSol is has a CM steel barrel/liner sleeved into an aluminum barrel housing. I would guess that the TacSol would weigh around 1/3 what a conventional steel barrel weighs.
Butler Creek barrels if I am not mistaken are "heavy" compared to Tac-Sol and other aluminum barrels......if the barrel is steel then your gun is going to be pretty front heavy. If you are shooting from a bench it wont be bad, but if it is going to be used for hunting it will suck....I have the hogue stock and a 16.5 Tac-Sol barrel and my gun is extremely light