Not heard about CA speakers before either, so personally I'd give them a miss and get some really nice ones second hand off ebay. The A5 is fine though, providing you get one that works, me and a mate hit a bad batch from the same RS store, and both had to replace ours, mine once, his twice, whereupon RS gave him an upgrade free of charge to say sorry.
You'd really be better listening to a CA A5 amp, to make sure you like the sound they produce, and then test them with several speakers to give you an idea of how different speakers play with the amp, some of the Richer Sounds should give you the option to demo the amp at least. For the price though, the A5 is pretty decent. Not amazing, but its a fair bit better than the Sony micro hi-fi I have that cost almost twice as much as my current setup cost me

Tbh, Im thinking of taking out the sony, and sticking it elsewhere in the house, selling it, or using it as a sound system for my consoles, because its doing virtually nothing right now, as I listen to my x-fi/a5/mission751 combo so so much more.