I'm no hunter, but I have had a Guardian 3 on my belt every single day for the past 2 years....it is the only knife model that I own two of (soon to be 3 once I get a wharnie!)
I absolutely cannot recommend them enough. Bradford is a really cool guy as well, once my sheath started to lose retention he sent me another free of charge. Edge retention on the M390 models is great. If you only plan on using it for hunting though, I would recommend the 4. The size difference is quite noticeable.