Esoteric Mods

I own an Esoteric P70/D70 Transport and DAC, I am considering having both modded. I have been doing some limited research, however I would like to hear from anyone who has had their Esoteric units modded to get some feedback. My units are still under warranty for another 6 months. I would like to know the names and websites of some reputable companies I can contact. Bottom line is it worth investing into. Thanks for your help