sounds like you should go balanced throughout your signal path. and maybe even shielded power cords (though usually shields sound bad on AC).
i'm not sure how EP2050 would take care of RFI / EMI, it may. it does have leads connecting it to hot (dual 30a breakers), neutral and ground, so its possible. i just dont know. looking at the 2750, it seems like it acts as the weizhi does (on ground), so could be a great product (the weizhi sure is). i will say that i still get improvement w/ R-C networks on the outlets, and the weizhi was a big improvement, so i dont know if the 2050 would be enough.
if i were just starting out w/ AC treatment, i'd go
1) dedicated lines w/ oyaide outlets
2) 2050 / 2750 in conjunction (have an electrician do 1-2 at same time)
3) RC networks on outlets (noise harvester sounds fine)
--i've no doubt this is more cost effective than anything else, and may get you there. but when it comes to AC, i've yet to go too far....hell, just today i reconfig'd my breaker box to have the 2050 on the same side of the breaker as my rig, added 2 maher CBFs as well, and it sounds fantastic (in the middle of the day in houston too---ie switching noise on hot is getting out of the story!). if you get the 2050, be sure to install it on the same side as your breaker, but closer to the incoming 0ga from the street than your stereo. i suspected this would help, and frankly my stereo sounds fantastic right now, 5pm, AC and dryer both on. ---i couldn't say that a week ago. (could be other crap on the grid not on, but i doubt it)