I like Tank 7 quite a bit when fresh. It loses some mojo over time for sure though. I had Saison Brett on tap in Chicago a while back and it had this weird fake sweetness going on and a very off-putting brett character I've not tasted anywhere else. Considering Saison Brett's reputation I just assumed there was something wrong with that keg.
That sounds like bad beer lines to me. There is no brett anywhere close to Tank 7.
I had ~4 of Boulevard's beers at a festival a few years ago. Tank 7 was one, there was a quad and two more. None of them really struck a chord with me. Based on that experience i've steered away from any of their stuff in the beer aisle.
Good. More for me.