I have both transmissions and really like each setup for what they are.
My PG has a 4 speed atlas behind it with a 2.7 range box, 3.8 main case, 5.13 gears and a 525hp LS2 from TKES. It's a great combo of race/ride/crawl. The thing I really like about the PG is it doesn't generate much heat. They are real easy to keep cool and cheap to build extremely stout. Aftermarket support is healthy for drag cars, keeping the costs down. I got mine from PTC through Wide Open Design and it was under $2000 with upgraded 1st gear and converter.
WFO has a TH400 and a 3.0 with 4.56 gears. It's awesome for grabbing quick wheel speed, good at trail riding but the trans does generate some heat when beat on for an extended period. I rarely take it out of low range. It does exactly what it was built for and I have zero complaints about the setup. It's strong, simple and dependable.
The only real drawback to a PG is the lack of a true 1st gear. Mine has a 1.80 gear set in it and it doesn't really pull for **** in high range. My ideal setup would be a 2.7 range box, 2.0 main box and 4.56 gears. That would crawl great in double low, haul the mail in 2.0 and bash between trails faster than most of your buddies if the buggy was set up for that. It would likely never see high range in the main case which makes shifting between crawl mode and cruise mode a simple and quick neutral rolling shift of the range box.
I am a PG fan for sure, not to mention they package easy because they are so small. Make sure you get it with the TH input shaft.