I have minimal experience with the recent stock ones and have seen a bit of variance. With the MJs at least you know what you're getting
Now here is where the fun is. Discraft was probably more consistent cause they made less than innova, now they are pumping a ton out. I also feel like they are tweaking more trying (and succeeding) to capture the disc collector market. I loved how every Z buzzz was the same. I did want a more stable buzzz option, like a couple glow runs were. Now I find a ton of Buzzz way more stable than those old Glow...
The kicker, Gateway is not tweaking their stock stuff nearly as much as they used to, have reinvested in newer machines and are pumping out one of the more consistent products. Smaller scale helps, but it's easier than ever to replace a stock disc with something similar.
Sad though, some discs lost their magic that special blends and runs used to have.