I dont have personal experience with the X-Bolt yet but I can tell you the triggers in the A-Bolt only adjust down to 3ish lbs. without a kit, and the one A-Bolt I own (338Win mag) has a ''squishy'' trigger and no overtravel adjustment.
I used to be a big Browning A-Bolt fan till I read up on them more, and talked to a bunch of guys on here about building mine. I think Ill leave mine as is and squeeze as much out of it as I can with handloads now.I still like it, dont get me wrong. Sometimes I listen to reason, sometimes I dont,(and Ill probably get LYNCHED for saying this) even the guys here on L/R/H wont ever be able to turn me into a Savage fan. Great for them if they like em' and thier rifle might out shoot mine, and might not, but Im a die hard Winchester fan. And thier actions are more easily buildable than Brownings A-Bolt. I dont know about the X-Bolt.
It all boils down to a personal preferance thing. If you like one or the other get it. But if it were me and Browning was the choice Id get the X-Bolt based on the trigger alone. Dont take this wrong. I still like Brownings too, someday Ill have a BAR, but for futre builds I know more now than I did before.