Tom, Garrets are definetly bad arse loads but Buffalo Bore loads the same weight bullets at even higher velocities.

Garretts 350 grain weldcore soft point is listed at 2000 fps
Buffalo Bores 350 grain jacketed flat nose is listed at 2150 fps

Garretts 420 grain cast hammerhead is listed at 1850fos
Buffalo bore 430 grain hard cast bullets is listed at 1925 fps

Their 500 grain bullets are about identacle at 1600 & 1625 fps

Unless you needed a tungsten solid bullet the Buffalo Bore cartridges are the more powerful loadings.They also happend to load some of the best 444 Marlin loads available.

http://www.buffalobore.com/ammunition/default.htm#4570