I'd go with the tapered barrel (I presume by "standard" you meant tapered). You're apparently trying to save weight by going with a shorter barrel so why then go with a heavy barrel? Also, in shooting numerous tapered and standard Encore barrels, I've found the tapered barrels to be very accurate.
Also, since you're going with a custom barrel, you might look at Match Grade Machine. I recently bought a barrel from them and have been VERY impressed with the quality thereof.