Yes some conditioners can be less than ideal for amplification.
I have a TX500 and I use it with everything BUT my power amp.
Just plug everything into it except your power amp or integrated amp and you will be fine.
I never tried the tx500 with the power amp. In my experience in the past with other conditioners, things sounded better (less constricted/ more dynamic) with the power amp plugged directly in the wall.
In my system it made a noticeable improvement. Noise floor went down, detail increased slightly. Dynamics were a bit better.
The other thing I did was run a dedicated 20 amp circuit just for the system with #10 wire. The improvement was larger than expected. I would say that in my system the dedicated circuit was just as big of an improvement as the tx500.
I put in the tx500 first, the dedicated line second, about 6 months later.
I'm guessing you won't hear of the magazines talk about dedicated lines because it does not help sell equipment and advertising.
Someone I know also uses a tx500 with a dedicated line and experienced the same improvements.
Put it in your system for 30 to 90 days. Then take it out and see if you notice a difference. Your mileage may vary of course but I'll bet you will like the improvement.
To some extent the improvement or lack of will depend on how noisy the incoming commercial power is.
Sure some may argue that brand x is better, but personally, I did not want to pay $1000 or more for a conditioner.
It was a great value and made a good improvement.
Hope that helps.
Regards
John