Some background & initial impressions...
It's been a long road that led me to the King. For several years, I had been trying to make up my between RoadKing/Roadster.
Second-hand RKIs and Roadsters were popping up frequently in my area but, somehow, I wasn't sold on either of them. Both seemed to lack something that I specifically wanted. I had played a Roadster so I knew how good its clean sounds were. The cleans on the RKI were...not quite as impressive. And, on the other hand, when you have an amp with so many different modes, it doesn't seem to me that having only 6L6s or EL34s would do justice to all of them. I would never be able to decide whether to put 6L6s or EL34s in a Roadster if I had one!
And then there was the RKII, which had neither of these limitations. But it was heavy as sin and cost a good bit more than either of the other two.
I was mulling over this year after year, until I made the inevitable conclusion. And I'm happy I did - I feel that I made the right decision, for me. If I had picked anything else, I would have been second-guessing forever.
Let me start by saying that the clean sounds are wonderful. Along with the Mark V, this amp has the best cleans of all Mesas I have. (Well, theoretically, the MkIIc+ could have at least as good cleans as the V, but you cannot dial in a great clean sound and a great lead sound on a Mark IIc+ because of the shared controls.) The Fat mode especially is immensely deep and resonant. Actually quite different from the Mark V Fat mode, which may have somewhat better clarity and definition but not that bottomless depth and richness of sound. Both are great, but I would say I prefer the RKII Fat.
Moving on to the semi-distorted/crunch modes, and continuing the inadvertent Mark V comparison, the Mark V would appear to hold an edge, since it offers 3 edge of distortion/low distortion modes (Tweed, Edge, Crunch) compared to the two on the RKII (Tweed, Brit). However, to take real advantage of those sounds, you have to put EL34s in your Mark V. This is where the Progressive Linkage pays off big time. Simply use those modes with a pair of EL34s...and get the Fat mode on 4x6L6 from the same amp. That's...just sick. Unreal.
And it gets even better when you move on to the more gainy modes. Vintage & Modern modes on six power tubes, 4x6L6 + 2xEL34, and 120W power deliver some of the most crushing Recto tones ever heard. Only a Triple Rec could compete with that.
Ok, I could do without cabinet switching (more cabs to lug around? no thank you, sir!) and the second effects loop. But Progressive Linkage...that's got to be one of the best features Mesa ever invented! It's like having 5 different power amps in a single package and being able to assign them on a per channel basis or switch them on the fly, as you please. I'm sad that Mesa hasn't put Progressive Linkage on any amps created after the Road King. It's a killer feature!
So how does the Road King compare, as a Dual Recto, to my old 2-channels?
Pretty well, I would say. No, it doesn't sound exactly like either of them. It's obviously closer to the G than to the C - but there's still a big difference. The King sounds smoother, more even and more modern. It is recognizably a Recto sound, yes, but compared to the G, it is like hearing a post-production track whereas the G delivers the more visceral, raw, 'unprocessed' version of the same basic sound.