I agree that the upgrade to the 2's is a good size one. Personally, the 2's is where Richards starts his magic in design. It's the base of the Vandersteen first order crossover and time and phase correctness. Yes, less smearing makes a huge difference in detail, size of stage and accuracy in general. Not only that, it physically has larger cones and will move much more air than the 1's. IF you can afford that upgrade, you will most probably love it. JMHO. Are you able to audition anywhere? Sounds like you may not be able to.
To me the upper line Vandersteen's best others in their price ranges. That's why I got the Treo and now the Quatro. They subtly give you more detail than most of the other speakers. Richard has learned where to make compromises in his products. The bottom line is that any speaker regardless of cost has to make these decisions. There are many flavors of speakers and it seems that most folks stay fairly true to their 'flavor'. That's why if you like a line, you most probably will stay within that line.
I've noticed that many companies tip up the treble 1-3 db (or more for a few) which gives an impression of larger sound stage and more sparkle to the speaker, but in fact that's not really what's happening. I PERSONALLY can't handle products like that as I get fatigued quickly. Unless we are in the production process we dont' know what is laid down on the tracks, so that makes it subjective.
If you like the Vandersteen sound, then you will love each upgrade in his line. As poster above said YMMV