Anyone had experience with PMC big guns?

I am interested in informed opinions, can anyone say a few words on differences between IB2 and MB2?
My main interest is the difference in low end performance, how do they compare in terms of resolution and apparent speed?
if you have the room and the money for 'big box monitor overkill' for the home, get a plane ticket to a dealer who carries both. i have heard both, but prefer the big spendor and the atc. you could import some duntechs and you're there, if a positive opinion is all you need.
Could you please describe in a few words the difference between IB2 and MB2, and why you preferred big spendor and the atc (and which models)?
If you are not happy with low end then it might be a placement or room issue. Assuming this is not the problem, then I am not sure the low end performance will be that different - it is the same TL design. I have not made a direct comparison - so I can't say much more.

FWIW: Many prefer ported or TL designs whilst a few prefer a sealed box type bass. If you want bass resolution and speed (very articulate and will give different sound on each track and such that you can discern the slightest subtleties between pressure on the hits on a kick drum) then really I'd go sealed box (in a critically damped or overdamped design) rather than TL. Many large ported monitors are designed that way - the port is not used to increase bass extension - it is just used for efficiency (allows bigger woofer motor in same size box).
the spendor 100(there's a brand new variation i haven't heard yet) doesn't know how to make any recording sound bad...if you're a record collector thats a good thing. In the battle of the big 'professionals', the atc bests the pmc in rock solid bass, and wide open dynamics. as for the 'sonic' difference between the two pmc's,I do n't think 'in most' households, the bass is going to sound that different. audio classics could be the place to hear both.
Sashav, you are home with the IB-2 and even more with the MB-2. But, the MB-2 throw huge bass that stomps over the most speakers. The MB-2 require huge room but sound is extremely fast, explicit detail that a great transmission line design give. The MB and IB are different in bass. Most resonable sized flats can't level with MB-2. I had IB-2 a Krell FPB 600c and the Teac P-70 and D-70 and it was awesome. The MB-2 was giving too much bass. The only gripe with Teac duo and the older FPB (c series) is that in the high frequency. The CX krell amps suits better with Esoteric or Teac, it is more organic. Or, you need to use a more soft sounding dcp than Esoteric/Teac. The IB-2 will not let you down, if paired up well. I've heard so many expensive speakers and systems. The IB-2 and MB-2 are really really great speakers. Just remember, the MB-2 will use a big amp, it will play louder and throw bass more than you might realize. If you got the room, go for it. I would buy the studio finish (black vinyl). The wood finish is not so good. It easily cracks and that is why i should opt for the vinyl trimming.