I'm no expert and only have limited experience actually firing both the HK91 and M1A. Personally, I've found the M1A (M14) to be more accurate and have a better trigger. It also balances better in my hands. The HK91 is heavier, but more rugged and robust. The HK91 feels more like a battle rifle to me, but that's purely subjective. Obviously the M1A has no pistol grip and is not like a traditional assault rifle. Also, the HK91 recoils more since it's a delayed blowback rather than a gas operated weapon. The HK91 can be a huge pain in the ass to field strip when the extractor spring is still very tight. After it loosens some with use, it's easy. I'm talking about stripping the bolt assembly of course. Overall, I'd guess it's personal preference. At this point in time however, I'd say the HK91 is much more collectable and worth more.