I use a 1-spot too, with no noted problems. Line 6 says not to, though.I power mine with a 1 spot with 2 daisy chains connected to 10 pedals.
Never once have I had an issue ever with my 1 spot or zilla.
I will admit I dont play games like powering on every pedal I own at the same time though. I leave that for other so I have something to read about here.
I dont have a verbazilla but I want to play too...and I DO have a line 6 echo park and a line 6 uber metal...
I tried powering my line 6 in a daisy chain powered by a 1 spot and it added HISS, not hum, but HISS
So I tried powering a boss noise supressor with a 1 spot and daisy chaining off of it, but again if a line 6 pedal was in there it added MUCH HISS
I powered a line 6 on my skb ps-45 using the power adapters and it added too much hiss...
basically the only way I have been able to power my line 6 echo park and uber metal without adding hiss is by using the line 6 wall warts...so far