^^^ I know you know way more about anything subaru than myself but the quote you have quoted doesn't seem to be the typical dangers of running a blow of valve.
Here is the actual stickied thread about blow off valves. A really good read.
*edit* upon further reading of the thread he talks about a leaky valve makes a turbo work harder causing premature wear on the turbo and higher egt's which over time can cause an engine failure
OP if it is a no name brand bov I would go back to stock, and have a local tuner check for some sort of aftermarket tune on the vehicle. The fact that there is a boost controller on the vehicle makes me think some one tried uping the boost and there is an aftermarket tune on it.
I would get rid of the bov not because it is a bov but it is a no name bov. It probably wont stay in adjustment and is constantly leaking. If you like the sound though, get one that has been proven to be a good unit.