Oh yeah, it's pinging.

I got impatient staring at my bottle of BG44K, so I put it in without changing the fuel filter first. All went well, and I think it made a minor improvement, but nothing earth-shattering... However, I have noticed a few short episodes of pinging, where the engine has almost no power but it pings when I lay down the throttle... Usually goes away after a few seconds and it's all OK again.
I'm at 49K, so my coils should be due soon as well. But I think these pinging episodes are fuel-related, based on the fact that they only started AFTER I threw BG44K in there.

 

As far as I know, you dont need to change your fuel filter when adding BG44K. Fuel filter on my 01 is maintenance free. I used BG44k last week and I got no pings. Still using the same octane gas from before?

 

Yep, same gas and everything.
I've ordered a fuel filter & O-ring from DaveB

BTW, about the Fuel Filter being "maintenance free"...
I know, the owner's manual says that and all, but that's a heaping load of if you ask me
No filter is maintenance-free, unless it's something insigificant like a cabin filter...
ESPECIALLY not a fuel-system-related filter

Also, it's not like it pings all the time, it's just infrequent... like maybe some dirt from the fuel filter became loosened by the BG44K and just clogged the injectors for a few seconds (possible theory)