Oh, yeah, pretty much any of those $600 subs will be better than that that cheap Infinity sub.
I personally don't think $3K for 3 speakers is going to sound "significantly" better than the BP30 after the HONEYMOON period is over.
During this honeymoon period, everyone seems to think their new shiny speakers just sound so much better than their old speakers and they can hear all kinds of things they "couldn't hear before".
There is a lot of bias.
You can get even get cheaper speakers that might have a better frequency response. But that doesn't guarantee you will actually like the sound better.
But if you have a lot time and energy (unpacking, repacking, and shipping big speakers is a lot of work), you can always try out these new speakers if they offer free shipping both ways.