MobiusStripTech did amazing mods for me twice. They worked on my ailing Virtual Boy and got it permanently running, I believe requiring internal soldering. Finally, both eyes reliably work! Then, to top it off, MST also modded my Atari Lynx, installing a new (beautiful, brightly lit) screen, along with a VGA port. Fast, reliable work, and great communication---highly recommended.
Mobius Strip Technologies has my highest possible recommendation. The ease in which I sent my PS1, got my PSIO installed, and the console shipped back was as good as it could possibly be. They were fantastic with communication and answered every question I had. The console was returned in perfect condition and the mod itself runs perfectly. They will be my first choice going forward.