Over the holiday I backtracked a bit in order to make a comparison. Without going all the way back to the stock outlet & 20A Hubbel, I did temporarily reinstall the Leviton 20A industrial outlet that I had been using previously to the Wattgate (also made by Leviton). After listening for awhile (I didn't previously recall there being such a huge difference between the two) the difference is even bigger than I had remembered.
Basically the Wattgate is just *so* much quieter: with better definition & separation between musical instruments & without the low level grunge & glare that almost sounded like enhanced HF detail (until I got used to not hearing that). However the most noticable & readily apparent difference is in bass authority: the Wattagate outlet really provides more slam, dynamics, even overall PRaT is much improved.
Yes $150 sounds like a lot for an outlet, but it's a cheap improvement sounding more on the level of a major component upgrade. Get a hold of one of these by all means - very highly recommended.
Now my next question regarding outlets.
What happens if I change the outlets in my Chang Lightspeed line conditioners?
Presently appears that they have Hubbel hospital outlets from the factory; after the Wattagate experience I'd be tempted to find out, but I'd need five @ $149; at list that's $750!
Maybe the Purist's etc would make more sense there, at least economically if not sonically?
Only one way to find out for sure - now where's my screwdriver?