I almost went with the then Phoenix Machine, now Defiance Machine, action with .750 bolt for the 338 Lapua Imp. A great action, no doubt.
But, by the time I looked at the extra cost for pic rail and recoil lug, that are already integral to the BAT HRPIC action, I just decided to go with the BAT. It seemed like the BAT would be stiffer and the BAT is quite lightweight (lighter than comparable Stiller actions) especially considering that the weight includes the integral pic rail and recoil lug. An integral rail and lug were two less things that I had to order and install as well and being integral, they were a couple less things to worry about as far as them coming loose from the action, not properly aligned, etc. BAT also didn't 'bat' an eye or charge any extra to program their CNC machines so the action would be set up for the 4.010" Wyatt's box. Just my personal experience so far.
Couldn't go wrong with the Defiance action, however, for sure.