Is there a reason you are only looking at these 2 brands? If you are still in Chicago area, I could provide some dealers info where you can listen to additional brands.
Based on what you have mentioend so far, for your listening experiences, room area and setup, I would go for a Thiel. I would call them neutral compared to B&Ws though the latter is also a good choice.
One thing with Thiels, they shine with lots of power - even monoblocks are a good option with Thiels. I have seen some of these go down to 1 ohm impedence when playing deep bass notes.
Also the 1.5 is a fairly older model. I would look at 2.3 or a 3.5 at a minimum. These are a much bigger upgrade over the 1.5s.
I would add atleast a 200 watts amp to get the best out of them.
Thanks, marsilians. I only looked at these two brands because the dealer had them. It would be great if you could point me to some other dealers in the Chicago area.