As is the point of the AAXPlosions, their transients will peak quicker, so would work better than the A as a cymbal for accenting.
For the same reason as above, when riding on it continuously, the AAX will have more definition for each hit, whereas the A will possibly blend/wash together a little more evenly.
As to whether they are bright or not depends entirely on the existing setup you're adding them to.
The bottom line is that they are both great cymbals, with minute differences which will them more or less suitable for your purpose - And that's the point. have a purpose for your next cymbal before buying it, and ask yourself what it offers that your existing setup cannot.
Hope this helps.