Stereo,
I saw where you mentioned stores in philly. David Lewis audio has the Thiels along with many others that he advertises selling.
Wilmington DE. has overture audio and HI FI house that may carry some lines you could here, (Audio Physics, Aerials, Sonus Fabor, Wilson, Krell, among others.
I currently own Thiels, Von Schweikerts, Aerials, Audio Physics, and some others all are much more dynamic then the ProAc 1sc including the Bulldogs, but will most likely not disapear like them, however the sound is huge compared to the ProAc so it becomes a matter of taste.
My opinion of the speakers that you are tossing around, although against popular opinion I favored slightly the Aerial 8b,s over the 10t with the type of music you mentioned plus ease of set up. I have not heard the vonSchweikert jrs. but own the VR-4 Gen iii and prefer my other speakers mentioned above. Dunlavy SC IV, nice but big and concern of driver availability. Thiels disappear well but are harder to drive and set up, but my CS6,s are very nice, maybe not the best for head music at high levels, but will nail the Jazz. The bulldog sound is not as large as the big Thiels, or Aerials, but do extremely well considering their size, but the tone and clarity, purity of the music in some ways are the best I own.
It also depends greatly on the size of your room they will be used in.
I,ve proably just added to your confusion, but alot of times that goes with this hobby half the fun is the search.
JIM