No. Particularly for HT use, but also IME for music. First and foremost a sub should be matched to the room. That is primarily a function of room size, placement and a sub controller. If you're using an HTR with audyssey or equivalent, the sub controller is already there. If not, think about the Audyssey/SVS or Velodyne SMS-1 subcontroller ($800, $450 respectively) or replacing your HTR with an Audyssey equipped unit. For my money, this is BY FAR the biggest bang for the buck in the subwoofer game.
Most of the "seamless integration" challenge is a function of smooth, carefully matched response through the crossover region, which is more a function of the items listed above than it is of any particular subwoofer. The only characteristic of a sub that -to my ear- audibly affects the match to a speaker is damping. Highly damped (usually, though not always, sealed) subs are often easier to match than ported models, unless the main speakers are underdamped at the crossover point. Variable damping models from SVS or Rythmik make life easier. Other than that, on your budget, there are lots of good choices (unless your room is HUGE). A new pair of 12" Rythmiks (my choice, but music centric) or SVS (highly regarded, probably better for mostly HT use) will be @ or < $1500. Both offer a direct sale, in-home trial, money back waranty.