I *believe* it's only from the A320 series onwards (A32/3/4/80)). The A300 series is an older, more conventional design (albeit with a very advanced AP for its age IIRC).
As with most things, I think there are benefits and drawbacks to both philosophies, but both are more than adequate for day to day operation. The argument for the traditional system here seems to be more geared towards a side-effect of that system in that you won't physically be able to put the levers in reverse unless they're both or all at idle, as opposed to the levers tracking what the A/THR is doing.
The A320 system is more like the speed telegraph system in the days of the ocean liner, requesting a speed from the engines (or A/THR) rather than directly setting it. It's a perfectly valid and safe system IMO, as long as you understand it.