shooting it is the only way to know if the wedge is set properly. If you shoot one group that is tight and then another that is all fliers it is likely the wedge. You can just treat the stock like a regular pillar-bedded stock by removing the wedge completely and just standing the rifle up on its butt while you tighten the two action screws.
As for bedding, I've bedded two accustocks and it definitely didn't hurt:
FCP-k:

one of the first 5-shot groups after bedding, the best its ever shot:
[img width=600 height=427]http://i813.photobucket.com/albums/zz53/bodywerks/accuwedge/best308group.jpg[/img]
and my 110 BA, still working up loads so have no groups:
[img width=600 height=448]http://i813.photobucket.com/albums/zz53/bodywerks/accuwedge/IMG_20100826_200740.jpg[/img]
[img width=600 height=448]http://i813.photobucket.com/albums/zz53/bodywerks/accuwedge/IMG_20100828_190804.jpg[/img]