PMC EB1i v. Thiel CS3.7 v. Pioneer S1-EX v. ???

I have owned IB2S and a number of smaller PMCs, and extensively auditioned MB2S, EB1, EB1i, IB2i, PB1i. There was a whole range of other speakers as well, bunch of models from well known manufacturers such as Wilsons (Max 2, W/P 7 and 8, Sasha, Sophia 1 and 2), Revels (Salon 2), Harbeth (Monitor 40.1), B&W (804s, 802d), Energy (almost entire range), PSB, JBL, the list is quite long, as well as some less known but promising manufacturers.
The PMC own midrange driver in IB2 and upper models is certainly better than what appears to be Vifa in lower models.
Each pair of speakers had some issues however.
I found that passive PMCs do sound better to me than passive ATCs, passive cross-over in PMC appears to be better design as it produces less integration issues, but active ATCs sound better than anything passive from PMC or ATC in corresponding range.
I have left the world of passive speakers, benefits are substantial.
So my order of preference in passive PMC arena is MB2S, IB2S, IB2i, EB1i, PB1i.
You will notice that I placed IB2S (the “professional” model) above IB2i (the “consumer” model), reason being that I consider PMC midrange driver the main benefit in lineup, much more so than the new SEAS tweeter found in “i” series, and I pay no attention to finish.
In other words, I would rather go up in “professional” lineup for the same money than going into “consumer” lineup, if you catch my drift.
This does not mean that SEAS tweeter is not different or would not be “better” to you, you would have to decide.

Sashav, may I ask how do you compare the active PMCs with active ATCs in their respective classes? The passive IB2i sounded pretty incredible to me. I can't imagine how much more the active models(PMC or ATC) would bring to the table when compared to the passive IB2i. Do you find the active PMCs or ATCs to be overall better speakers than the Wilson Sasha and Revel Salon2? A friend of mine owns both these speakers -Salon2 in his main system and Sashas in his bedroom.

I am also familiar with the Harbeth M40.1s. As good as this top of the range Harbeth can be, the philosophy in the design of this speaker is different from the equivalent range from PMC and ATC. The bigger PMC and ATC passives or actives are made from robust heavy duty drivers built in heavy cabinets whereas the cabinet of the 40.1s are made from "thin-wall" panels. I believe the bigger PMC and ATCs possess a much larger scale with higher SPL capabilities than the 40.1s(or any other speaker for that matter). The result is a highly controlled and composed sound with high degree of transparency and the ability to play at crazy volume levels(probably in the excess of 120dB in a large space) without losing control.

Sashav: You have a wonderful breadth of experience with fine speakers. Thank you very much for the detailed descriptions; they're quite helpful. Like Ryder, I'm also interested in your thoughts comparing the Wilsons and Revels to the PMCs, especially the IB2S/IB2i.

I cannot offer at this time a meaningful comparison of active PMC to active ATC, but I will be able to do so in a month or so when I will have them side by side.
I owned IB2S and have auditioned IB2i, and I agree that IB2i sounds incredible, but active ATC50 is overall more incredible to me, considering that there is no perfect speaker and all have some shortcomings.
So far my preference has been passive PMC over passive ATC, and active ATC over passive PMC, overall, based on models I have heard.
I find active ATC to be better than Wilson Sasha and Revel Salon 2, I also prefer passive IB2S or IB2i over these two, but I must say that Revel Salon 2 is also extremely well made speaker with very good integration of drivers, and I prefer Revel Salon 2 over Sasha considerably. About the only thing I find objectionable with Revel Salon 2 is a slight metallic coloration which I guess is the consequence of materials used. And I prefer Revel Salon 2 over lower PMC models.
I agree with Ryder’s assessment of Harbeth in comparison to PMC.
Finally, you will notice that I speak of my preferences, your ears should ultimately guide you.

hi Bill
First off,good luck with your speaker hunt and have fun.
Going by your room size,17x28,you would have no problems with MB2 or IB2.And depending on your average maximum volumes(110-120db??)the midrange would play a big part.If your max. volume does not "ever" exceed 110-112db,the vifa mid will work.Dont get to caught up in the "i" tweeter as it is not worth the extra thousands of dollars they ask for it.You can find a good used pair of non "i" MB2/IB2 for the $7-$8000 range with stands.