"...both are FL dies..." Yes and regular FL dies have been around far longer than SB dies. An SB die just sizes a bit smaller. Some people think you absolutely must use an SB for semi's, pumps and levers. You don't. Either one will do.
As to a 7600 being finicky. Nearly every rifle Remington makes, other than the 700, tend to be finicky. Some people swear at them. Others swear by them. Some will tell you what junk the old 742/7400 is. Usually a maintenance issue with either it or the 7600. The ones that swear at them usually fess up to trying to shoot them rapidly as often as possible. They ain't made for that.