I have just had my ls25 upgraded to the mk11 version, I was using nos tubes that made an incredible difference, I have not had the chance to evaluate them side by side but so far it looks like it's going to be a tight race. I would compare the two before doing the upgrade and keep in mind you are limiting yourselves to just stock 6h30's since I don't believe anyone else makes them, I did not think about the tube limitations before I had the upgrade done. just my opinion.
