I'm no Mike C.. but:
I think MVP plastic lasts longer because they resist warping and the polymer they use has much less memory compared to other plastics. So when you hit a tree or bend the disc in some way, the disc doesn't "remember" that bend or taco after it hits something. MVP likes to hold its shape very well and resist stretching. I have an old MVP vector that has been abused since the day it was released, it still has its shape, its still flat when sat on the table, there's no wavy edges, there's no big gouges or slices like my star/champ might have and most of all it still has some stability and isn't flippy.
Low Memory is what you wantand MVP delivers that.
not to dismiss you out-of-hand, but, um..no.
And MVP discs don't "last longer" than other discs. They are plastic, and will more or less last forever anyway. So keep them out of the landfill you dirty polluters!
I digress. My MVP discs, as I previously stated, have scuffs, dings, chunks and scrapes. They might be a slight bit more resistant, but I agree with Mike C and say it's a toss up between Neutron, Champ, Z, Opto, etc. I don't agree that MVP discs are more durable, but I agree they hold their flight characteristics longer. And I don't think that has anything to do with the plastic memory, which is really just the amount of flex in the molecules are something like that.
So while I understand what in4d is getting at (it's not just nonsense, by the way...it's truth but neither he nor I know the technical terms) I'm gonna stick with Gyro Tech for my answer.
sorry for the thread drift.