SUBsonic SUBserviency.
Hi blue star,
Cannot say honestly. I just look at their specs, but that won't tell me much about their tightness.
But for your home theater, perhaps the Boston Acoustics with it's 10" driver and bigger box and bigger weight, will fill your room better.
The Def. Tech. with it's smaller 8" driver might prove a bit too small for a sub! I think that the Def. Tech. ProSub 800 is more suitable with small satellite speakers.
I found a review for the ProSub 800, but I was not impressed at all. But if you want to have a look:
->
http://reviews.cnet.com/subwoofers/definitive-technology-prosub-800/4505-11312_7-33066920.html
If it was me, between these two, I'll go with the Boston Acoustics HPS10HOMIST.
Here ->
http://www.testfreaks.com/hifi-subwoofers/boston-accoustics-hps-10ho
Did you try to Google them to see if you can find some reviews?
Is there other brands available in your area in that price range?
Bob