Hey Zuter, Welcome...
Yes it is important for your center and left/right speakers to be matched. This will help give you a better soundstage and seamless transition.
I had some Klipsch floorstanding RFII's at one point. A friend of mine now owns them. At the time I thought they were great, because the speakers they replaced were very cheap infinity bookshelfs.
I then upgraded to Axiom m60's, which were in a whole other league from the Klipsch's. When I decided on m60's, they were compared against B&W 703's, Paradigm Studio 7's, and NHT ???. All of the 3 above were also better than the Klipsch.
Klipsch is a good Retail type speaker in my opinion. The HORN sound is not for everyone. If you want clear, accurate, detail of your music, then I would look at a dome tweeter design.
Many people will tell you Axiom's are bright, and compare them to Klipsch. I just don't see that explanation as being true.
I currently own m80's for my mains and most likely will never change again, that is until they come out with m100's.
I would also suggest you check the audition thread to see if you can swing an audition in your area. That is all it took for me.