The 30.2 is not identical to my Yamamoto A-08S which shall stand in as one example for a superior modern low-power SET.
But I'd say that the 30.2 now is playing "on the level" with it. Bass is far better as you'd expect and it's actually warmer.
The Yamamoto has more energy in the mid to upper treble and when it comes to that vocal sex thing (whatever you want to call it but I reckon we all know what I mean by it), it still has the edge over the 30.2.
The big flipside of course is that the RWA uses
- no tubes
- can drive speakers the Yamamoto can't even dream about
Which, to me and at the end of the day, makes the 30.2 a SET-like (but not SET-same) and nearly universal recommendation. But it's not the same yet and perhaps never will be since, I believe, part of the SET magic is a certain unpredictable non-linear behavior which someone, elsewhere, called "artificial intelligence". By which he described SET -typical behavior where the amp carves out the lead vocals while it sets back the accompaniment a bit in importance.
That kind of editorializing the Signature 30.2 does not do and I don't think any transistor amp will (unless, perhaps, it's got high output impedance *and* an output transformer)...