I've been using Redline MTL in all of my cars with manuals, except the Pantera. I just haven't got to it yet.
Gary Hall told me to try it a while back and I can tell you that it is a very interesting formulation.
It makes shifting easier but more precise, like it was a new gear box. Frankly, my ZF could use a little of that medicine.
If you go to their web site you will read the reason it is made. I suppose to paraphrase it, it is fully synthetic gear lube, with special friction modifiers added for the synchros.
See. Full synthetic gear lube is too slippery for your synchros and they won't slow down the spinning gears properly. It's kinda like oiling your brake pads. The pads need friction to work.
The MTL has those friction modifiers and makes the trannie feel tight and precise. Like I said, my ZF can use that.