they are good guns. he will not be disappointed with it. few things to keep in mind, if he's going to do alot of clay bird shooting or light load ie doves then the 3.5" may not be a good choice because it won't cycle loads under 1 1/8oz 100% of the time. if the majority of his shooting it going to be heavy loads or 3", 3.5" then there's no problems. if he's not going to be using alot of 3.5" shells for the ocasional goose or turkey hunt they save yourself and get the 3" gun.
winchester lighened the x3 by alost a pound over the x2, so the x3 will kick more. they finally added the stock shims to customize the fit. the gas system is great, nice a simple, amost as good as a beretta.

i won't not spend the extra money on a gold. 1. the only things different is the gold a a mag cut off that you'd probably never use and a little different bolt lock.2. the gold is done with after this year. browning is rolling over to the silver which is a hybrid of the classic hunter and the x3. there are rebates out on golds right now for dealer who still have them on there shelves.

i like the x3. i have 2 x2's but the beretta is also good, IMHO a bit better.