The Sunfire approach (small cabinet, big amp) is not for everyone. I can't speak to the specific model you're considering, but - in general - subs using this approach tend to produce a lot of THD at high SPL/low frequency (relative to larger cabinet subwoofers). Neither do they particularly distinguish themselves (as a group) on group delay - the test some folks to use as a proxy for "speed". So, for the quant types, these designs my not hold a ton of appeal.
To be clear, that's a general observation from reviewing test data across a lot of these types of subwoofers - not a specific comment on the TSEQ12.
One reason you see a lot of Rythmik (I use a pair of their 12" subs) and SVS recommendations is that both brands tend to perform unusually well on both tests (SVS better on clean output, Rythmik better on Group Delay). Another reason IME (for Rythmik, at least) is that they sound great.
Marty
To be clear, that's a general observation from reviewing test data across a lot of these types of subwoofers - not a specific comment on the TSEQ12.
One reason you see a lot of Rythmik (I use a pair of their 12" subs) and SVS recommendations is that both brands tend to perform unusually well on both tests (SVS better on clean output, Rythmik better on Group Delay). Another reason IME (for Rythmik, at least) is that they sound great.
Marty