I'm still finishing up the building process, so I can't speak of on mountain performance yet, but I can say that if you have the patience, splitting your own board seems the way to go. Factory splits are just too expensive and with a custom split you get to choose any board you want instead of being limited to the minimal selection of factory splits.
A couple notes on building:
1. when splitting the board, make sure you file all the way through the edges so the blade doesn't catch and rip it out. It's set in further than you think so use a dremmel or something if you have to.
2. i decided to replace the puck screws with 1/4 by 3/4 long bolts with 1/4 t-nuts on the back instead of the wood screws with epoxy method. if you use a forsener bit to countersink the t-nuts you can p-tex right over them. i think this will be much stronger. if you want to ride hard and drop cliffs in the backcountry, don't get stuck 5 miles out with a stripped puck mount, use a t-nut.
3. also, don't try to split a burton, the burton binding insert pattern has metal inserts right down the center so it'll screw up your cut.
i did lots of research before I had the balls to chop a board in half, so hopefully these tips will help.