As a new Navy NSM in 1980 we were issued with 7.62 FN FAL (Belgian made, wood furniture, no blitzbreker). Good, solid, proven. Shot only once and hated it.
Mustered as a Marine and issued a brand new H&K G3a3. Story was these were "captured" in harbour raid by the Recces in Angola.
Most of the guys new nothing about the G3 and there was talk that it was Russian. No-one new how to dissassemble/clean it and no instructor in Saldanha or Potch had any knowledge of it. Well engineered, (stampings and plastic furniture, aluminium mags). Carried it constantly. Some of the Marines "just happened" to break the stock to get it replaced with a R1 (local FN FAL). Towards the end of training we received the then new R4. I later shot the M16, R5, AKM and Lee-Enfield.
So without going into the weight/length/calibre/mag capacity issue I offer my opinion on the soldiers thinking.
Telling a troepie that his rifle has a bottle opener on it, a bipod, a 35 (50) round magazine, folding stock, night sights, better ammunition? etc is great.
A troepie must feel proud and confident in his weapons capabilities and any "new" weapon is immediately the "wonder" weapon.
My feelings
FN - Hated it because it formed part of basic training (marching, drilling D-formation, tear smoke etc). It had long lost its blue and rusted at the first opportunity. Had to be constantly cleaned and since we only shot it on one occassion, it seemed just like another form of punishment. No sling supplied. Unless the gas regulator balanced, repeated stoppages.
G3 - Loved it. Brand new. I new the weapon and its history, Could operate, strip and clean ( a bit more difficult to clean than the FN). Since I now had a modern(newer) rifle and my life could now depend on it, I took more care of it and respected it more. Although it was about the same weight and length it "felt" lighter. Shot it many tmes and found snap-shooting and low light shooting easy. Never had a stoppage. The aluminium mags did not last (basically meant to be thrown away). The front hand guard (slim) got hot during rapid fire.
R1 - In Potch some Marines managed to bend the G3 barrels, shot the Blitzbreker off and break the stock. This was done through ignorance or wilfully as they wanted the R1 which looked newer and more dependable. Again balance the gas and you have a dependable rifle.
R4 - Bells and whistles. A good dependable rifle. Would sometimes go bang when it was'nt meant to (mostly driver error, but also a firing pin that was slightly too long with no return spring). Folding stock meant it was easier to move around/transport. When the carrying handles were removed, not easy to carry comfortably without the sling (thank goodness a wide sling). No stoppages
R5 - as above. Did'nt miss the bipod. But easier to carry.
The others - M16 etc. Should not really comment as I only shot them, did not carry them. But all decent weapons.
To sum up. All weapons are good by the time they reach the troepies hands (except the SA80 which needed H&K to make it reasonable). A lot has to do with the troepie being confident in the weapon and its abilities. I think this is the biggest factor. Look at the negative attitude towards the M16 when it was issued (stories that it never needed cleaning and then the US issued the troops in Vietnam with ammo leaving high residue) and the SA80 that only the British could design and not accept was a piece of %$#&. The AK (and clones - R4?) may be dated and a symbol of Soviet power/terrorists etc. But it has been used worldwide (and by special forces nogal) and is still being manufactured in various guises.
My choice --- The G3
Like your wife, you look after her and she will be by your side when you need. Like your dog, give it the right food and it will be dependable. Like your car, clean and service and it won't let you down. But like all of them sometimes you need to upgrade.
GOTTA GO - wife just read this!!!!!!!!!!!!!!
Added pic of three rifles on the step of our bungalow at 3SAI Potch early 1981. The R4 had just been issued to the new Jan intake infantry. The R1 was being issued to us Marines as the G3's became unserviceable. And then in front, my G3a3.
And then a pic of myself in full kit about to go to asgate or the range. Th smile didn't last long. Again my G3a3.