I am a fan of Canton speakers which use their Ceramic tweeter; however, I am less enamored to their aluminum tweeter (it is not bad, but nor is it great). All Canton speakers seem well engineered, and reasonable speakers for the price ... but it is the ceramic tweeter that makes them special, IMHO. The ones you are looking at have the aluminum tweeter.
I have never heard RSL speakers, but they have a good enough reputation that I doubt you will regret them. Additionally RSL has a great return policy if they don't work out! Accordingly, I vote RSL as the safer bet!