I have not in a Mesa and the prevailing thought is Mesa uses good iron unlike other amp companies.
I switched the stock Dagnall in imy Marshall DSL50 with a Mercury Magnetics OT and it made a good platform great. I'm not a believer in advertising, but the claims MM made on there web-site proved true to my ears.
I'd love to do it in an older Rev G 2 ch just to see what the effect would be. It's been talked about on here but I don't recall anyone actually doing it. If there's a post someone please throw it up.
