I have a 2006-2009 type X-Mark Pro trigger on my 2008 Remington 700 BDL (.270 Winchester). Here is my experience with it.
From the factory there was no sealant on the pull weight screw, so I had no trouble accessing the pull weight screw once the stock was taken off. I special ordered the rifle and it was not 'tinkered with' before I got to it, so I know it came from the factory this way. The other two screws (not meant to be adjusted) were sealed with a clear sealant.
Out of the box it had no creep, a nice crisp break, but was a bit too heavy. Maybe 5lbs. Turning the allen-headed screw for pull weight outward 1 and 1/4 turns reduced the trigger pull about 50% but I do not have a weight gauge. Turning it out 1 and 1/2 turns resulted in a bolt that would occasionally not cock. 1 and 3/4 and it didn't work at all.
No creep, very crisp, clean break, little over travel. Feels good.
For comparison, my father owns an early Remington 700 BDL with the old style trigger (3 screws). Its trigger had never been adjusted, and it was MUCH worse (lots of creep) than my out-of-the-box X-mark Pro trigger. I had to remove amber-looking sealant from 3 straight-head screws, which was easy because the sealant was old and cracking. After adjusting all three screws, the final results feel quite similar to my post-adjustment X-Mark Pro trigger.
Don't fret if you have the 2006-2009 version instead of the new easier to adjust one. It is still good stuff. Dropping the trigger weight down isn't something you do every range outing, and it's easy enough to do on any of them.
And if you really want an awesome trigger, go get a Jewell.