I use this EQ to ring out mics on my analog PA. I use a visual spectrum analyzer to ID problem frequencies, and use a channel on this EQ model for every channel with a mic to kill potential feedback problems during stage/FOH soundchecks.
I cannot speak to it's feedback detection features, as I do not use it, I prefer have a dedicated visual spectrum analyzer. (Fun generation RTA-31, sold here at Thomann).
Price to performance, it is on point. Can't see a reason to spend more for an EQ unit. This one also sports an adjustable cross-over, for those using it to EQ a main PA output with it, though i cannot speak to that features' performance, as I do not use that either...
I'm happy with these units. I now own 5 of them. No problem so far.