Tact 2.0S or Tact 2.2XP

I'm looking for a room correction device to cure the bass boom I'm getting in my room.
I've CD and Digital source(Bryston BDP-1) and have external DAC and pre-amp from Bryston.
I don't have any sub-woofer and don't want to use any in future.
It will be connected through digital interface so I don't need any add on cards ... basic unit will do.
But my question is what is the difference between 2.0S and 2.2XP other than sub-woofer connectivity and PC free setup in 2.2XP.
Shouldn't I get the auto room correction and Dynamic room correction features in 2.0S? What will be the problem without those features?
Please share your views.
Before spending a ton of money on signal processing, try room treatments, and understanding of what is happening in your room. Read Jim Smith's 'Better Sound' as a first step.
The 2.0S has been discontinued because newer, faster processors have become available, however for the price difference you will still get all the basic room correction, plus a bunch of nice features that it will take a while to appreciate. No amount of room treatment will accomplish as much, or let you try alternatives while you can still compare the results directly.
All that said, you must be wiling to be patient and learn over time, with a good bit of trial and error. Folks who think they can plug and play will be disappointed. I started with a 2.0, traded up to a 2.0S and then to the integrated 2150XDM. I am still trying out new settings and curves.
The 2.0S provides the same room correction as the 2.2x, but without the sub x-over feature (that you apparently don't want). The xp version adds the Dynamic room correction feature, that may or may not be worth the extra money to you, as well as the ability to make changes on-the-fly without a computer. I've owned the 2.0S and the 2.2x (with and without mods) and decided to spend my extra $$ on mods rather than the Dynamic room correction feature.
You won't get the Dynamic room correction feature in 2.0S. Whether you'll miss this is hard to say. If you want to be able to make and compare correction curves on the fly, go with the xp. If you want better sound and are willing to put up with less convenience, go with the 2.0S with a power supply mod, and possibly digital input and output mods. Or spend more and get it all.
I find room correction indispensable and unequalled, esp. in bass control, as I'm very sensitive to bass nodes. Room treatments can and do help, but IMO, won't replace what the Tact can do (I still use bass busters and absorption, and diffusion).
If you get the 2.2xp, you owe it to yourself to at least borrow a sub or two and hear what they can do in a Tacted room. My speakers are rated -3dB @ 20Hz and still adding Lyngdorf corner subs provides a huge benefit.
Thanks all for the feedback.
@Samujohn ...Tact 2.0S is still in their web site and new Tact 2.0S incorporates new features:

The 2.0S brings the processing power of the 2.2X to the RCS 2.0

Digital outputs are user programmable to output at sampling frequencies up to 192kHz

Digital inputs accept signals up to 24bit 192 kHz

ParaEQ is now included as a standard feature

A/D and D/A converters have been upgraded to the specifications of the converters found in the RCS 2.2X

@ Richards ... Thanks for your insight.
My room is small 11' x 16' feet and using Dynaudio Sapphire, bass is not always boomy but in some materials it create boom otherwise I like the bass and I feel I don't need any sub-woofer. I played with speaker placement and I come to a dead end, in my small room I cant pull the speakers any further into the room.
I've read reviews and user feed back on Tact and I am convinced that the Tact will serve my purpose.
There is a feature called Auto Room Correction in 2.2XP, it will be convenient to adjust Tact with this features ... some sort of plug and play and I wont get this featues in 2.0S.
I've seen lots of frustration setting up Tact 2.0S .... is it possible to set up the device without any additional device?
BTW I don't have any option to get it modded as I live in a remote area.
Thanks once again for all of your responses.