The Imagine T really has no low bass, so you will need a subwoofer in either case.
I had the Image T6 speakers until recently, and they have more real bass than the Imagine T (the specs are misleading) and I still ended up deciding to get a subwoofer (the NHT B12D, which is the best I know of for Under $1000).
The Image T6 is a very good speaker; I listened to them for two years and never heard anything I didn't like out of them. They actually outperform the Imagine T in many ways.
The speakers I have now are SO much better than any of the above, however, that I wouldn't want go back to any PSB speaker with the possible exception of the Synchrony One.
They are the Gallo Acoustics CL-3 and they are just amazing. They are a lightly smaller floorstanding speaker with amazing sound quality, and bass, and power, for their price.
I was considering some Dynaudio and Vienna Acoustics speakers in the $3000 range when I first heard the Gallo speakers, and I was amazed; I had to have them!
The amazing thing is that they are Only $1595/pair, which has to be the bargain of the century. I highly recommend them. The current issue of The Absolute Sound has a rave review on them, and their high praise is still not enough to convey how good they are. Their power and bass equal or surpass all of the PSB speakers too, which is almost unbelievable for their size (31" tall and 8 inches wide).
Their pristine sound quality comes very close to my Vandersteen 3A speakers at my other house (which cost almost $5000). They are also VERY attractive!
They are being sold direct with a 60-day free trial period (shipping paid both ways), so try them and be amazed like i was.
Edited by commsysman - 7/2/12 at 11:47pm