Do you have a sub with your current setup? Typically with newer systems you don't need your speakers to handle all of the bass(not base, btw). You would just make sure that your speakers would go low enough for the sub to take over. This will allow your speakers to focus more on mid and high frequencies and overall you would get more and deeper bass because of the capability of the sub. So try not to focus a lot on the very low end of the towers you listen to. Maybe even demo them with a sub a little bit. Since subs are more prevalent these days, it is a little less common to find towers with dual 8" woofers. You could also try going into a Best Buy/Magnolia. They will have a decent selection of speakers in the range of the Paradigms. As far as Salk is concerned, it doesn't look like they have dealers. At the very least, their website is very unclear. It looks like you can only purchase direct, but they do not list a return/demo policy. Your best bet is to find a forum member near you that is willing to let you listen to theirs. You can listen to higher end models and get an idea of what the lower end ones sound like. Be VERY careful though. They should be at least similar to what you are looking at. Same tweeter/driver technology. Similar driver configuration(i.e. 2 way, 3 way). Similar tower design, so don't listen to tower if you want the bookshelf. Also, if you are going to do this, make sure you have some sort of return policy that allows you to listen in your home for at least a couple weeks.
Though I am an employee of Magnolia Home Theater, the views and opinions I express on this forum are those of my own and not my employer.