I haven't heard much good about the outlaw chassis by people wh ohave actually built them.
The ultimate would be a Laeger chassis. They are no longer made, unless your name is Eichner. You can still find them floating around, but price better not be a concern.
Elka does not make a Banshee link, and as far as I know, Gibson does not make longtravel for the Banshee.
And there is no testing method to "prove" any suspension. Roll is a top tier company. Look at who makes Banshee suspension, then look at the Pro class at your local race. Of those you see that make Banshee parts, Roll will be one of the most widely used.
There's a reason people choose them. It's certainly not price.
You can argue that they are not as much better as the price is higher. It's debatable. But to say they are no good or not proven is wrong.