charles daly 3.5 camo mag 12 gauge semi-auto?

i recently sent my 12 gauge back for repair ,,they fixed it and works good,but i hear a lot of complaints ,,actually read ,that the locking block on these autos is the problem,,suppose to shoot 2.75-3.5 shells it said flame throwers ,,i cant get it to shoot 2.75 ive tried all but f ioci 4 dram really expensive verses 3 inch i wanted auto to shoot 3 -3.5. but 2.75 s would be nice on the occasion id want to shoot cheaper rounds gun throws marvelous pattern hardwoods camo ive seen the new winchester 1300,00 to expensive the new tristar,,baikal at wallworld they say adjustable to shoot weaker shells black only what do you think ,,,,,should i keep and take chance or sale when working good ,,so maybe it wont keep me from missing bird season again;;;;;