I have not heard the above. However, the A300 is cleaner and has better "air" surrounding the vocals when compared with the A3 int amp. The sonic difference was well worth the price difference.
I have been using the A308 int for the past year. I originally bought a A3.2 CD player and I was considering the A3.2 int, but the 308 is in a different league. It delivers very clean power. The sound stage is much better than the 3.2 - very wide and deep. It also presents a dark background that gives you a sense of spaciousness. I agree with the review from Soundstage.com. Couldn't be happier with my choice.
As it happens, I have a 3.2 CD player and an a308 integrated, like Eyeballman. They go with Triangle Celius speakers and moderate cable and interconnect.
Anyway, if you are going to spend more on an amp or a cd player, make it the amp. Unfortunately, I cannot compare 3.2 integrated to a308. However, I love the grip the a308 exerts on my [admittedly sensitive] Triangles. Also, the 3.2 CD player goes well, indeed perfectly, with the a308 integrated. The a308 integrated is just a beautiful piece of metal. Spring for it if you can.
I ended up getting the A308 and there is a marked difference when compared to the A3.2; better lows, better sounstage not as bright and I am no longer getting the listener's fatigue I was getting with the A3.2. The bad news is that I have a disease that makes me want to upgrade every six months or so... should I listen to the trivista or the new A5.. gotta go my wife is ready to kill me!