It will be money well spent. AV123 has an excellent reputation for value/performance and customer service. Do a google search for "Rocket by Onix speakers" and it will link you to reviews and discussions about them. A google search of Mark Shifter [founder&pres] will also give you another perspective and most certainly more confidence in the purchase. Mark has contributed a lot to the audio community and is highly esteemed.
The RSC200 is an exceptional center channel. A common comment is how certain passages that were hard to hear are clear thru BigFoot, as the 200 is aptly and affectionately known. I haven't heard the 550's [I have the 750's/200/300's] but have read a lot of good things about them from happy owners. The business model of the internet direct companies that have gained support among the audio community did so by offering great products for great prices. They had to offer more than "brick & mortar" stores or they couldn't compete. Surprisingly or not, the customer service that the more successful companies deliver is outstanding. Problems when they occur are taken care of quickly. These companies can't afford bad ink on the forums, because these are the people that are their lifeblood. Plain and simple, if you don't deliver on the internet, you don't stay in business. The hopes of the customers are high, and their expectations are usually exceeded, as I've read again and again and experienced myself.
Have you checked on AudioEnvy.com to see if anyone in your area will let you have an audition in their home? If there is nobody listed near you you can also post at the forum at AV123 where some people who aren't listed on audioenvy will also give you an audition.
Of course you can just pull the trigger and try them in your own home with your equiptment although if they are not to your liking you will be out shipping costs. You can try just the center and keep down the shipping costs, but be warned you might be sorry you have to wait for the mains.
TinHere (& flafonta if you purchased the Rocket 550s)
I am thinking about the Rocket 550s. Recently I have listened to the following speakers:
Boston Acoustic VR3s
Monitor Audio Silver S8s
What do the Rockets sound most like? What characterestics would the Rockets share with any of these speakers? What characteristics of the Rockets would be opposite of what any of these speakers would have?