The ACT one seems to be the one that most people say is the best. I would probably agree with them. Don't rule out the X10 Pro XPCR though. It's a very good unit that can handle either 2 or 3 phases. With these being on sale now at a large discount from the ACT model, that's the one I would probably consider.
The ACT one is also better in the rare case that your house that needs multple couple/repeaters. The ACT unit has a lot of setting for helping them work together more smoothly.