The HK33 never got a real decades long product improvement program like the M16 series had. As a result they seem kind of etched in stone in what is very close to their original 1960's era form. The G41 was probably a regressive design, which I consider inferior to the HK33, despite the best of intentions. Lipstick on a pig, and the pig was better looking without makeup.
I think a fair comparison is a late 1960's/early 1970's M16A1 rifle with iron sights and aluminum mags. I'd take an iron sighted HK33 with it's OEM mags over that. That's my opinion. The M16A1's I have had experience with, both in the army and early on in my agency, were pretty bad.
Navy Seals used HK33's in Vietnam, at a time when Special Forces and LRRP's had assembled rifle rods taped to their CAR-15 foregrips to clear catastrophic failures, while under fire. Whatever it's faults, the HK33 is robust and tolerant of abuse.