spas 12 & 15 are great guns.
I'm partial of course because I actually own two spas 12s that work all the time.
The reliability complaint that people talk of is nonsense. The people who actually accuse this gun of not being reliable, I doubt they have much time with them. Show me one that doesn't work, and I'm certain you can find what is wrong with it very quickly. You put the mag follower in backwards, it wont feed.
You lose the O ring, it won't work in semi auto.
You use real light loads, it's not going to work in semi auto either.
Gun still won't feed? Maybe it's your reloads and they're all bulged up crummy old shells that arent even close to being circular at the front. So they'll have feeding problems.
They can get very dirty firing them in pump mode and not cleaning around the gas ports after about 500 rounds if you're using a dirty powder such as PROMO or Green Dot. That will lead to problems being able to move the selector from pump to auto. Get a tooth brush and some wd40, spend 5 minutes, and you're good as new.
Breakage? Well considering the one I shoot all the time was my very first gun 13 years ago, and still my favorite to shoot, parts replacement has been minimal, far less than i've seen replaced on remington 1100s which were heavily used alongside my spas 12 in skeet competition with much lighter loads than I liked shooting.
A shock buff, a firing pin, a rear sight screw and one other minor part that surrounds the pump/auto selection button is the only thing I've had to replace after well over 100,000 rounds.
Heavy and bulky? It's only 10 pounds, which is basically the same weight as an over under skeet gun with a tube set or a barrel weight. Most of the weight is up front though, which leads some to think it's heavier than it is.
are the ergonomics difficult? Not at all, everything is close to where you place your hands and quickly and easily operable. But it is not a gun you pick up and know how to use in 5 minutes.
The metal folder- not fun to shoot as it's just painful to put your face against that metal stock and fire off some heavy 12ga.
Still if you're a fan, you need one of these too.
Spas 15- even better, but expensive, (3-5 thousand range) and mags are ridiculous in price.
Wish I had the money to buy my friends when he decided he wasn't going to shoot 3 gun anymore.