hmmmmmm it depends what kinda thing you had in mind for it.
the AD30 will do mid-gain kinda jangely garage-rock stuff all day long and really just about anything you throw at it (though you might need a pedal if you want uber gain) and is a pretty rad amp... (i have the custom shop retro 50 head thats somewhere between an AD and the vintage OR's and its freaking awsome...) also if you look used you could find the single chennel version with reverb if thats what your into.,.. no effects loop. 2 channels are *basicaly* the same on this one
the rocker 30 is also a KICKIN amp... 2 channels (but relize the clean channel has ONLY a volume knob, no eq.... but thats ok because its voiced really really really well) and the dirt chennel has regular eq on it. more gain on tap than the AD and smaller in its 1x12 vs. 2x12 form. no reverb no fx loop.
basically the AD is a little more vintage and the rocker is a little more modern but both kick mojor ass and i dont think you would be dissapoined with either.... id stay away from the TT just because if you have the coin for the bigger brothers i def think its worth it... the TT sounds (as far as im aware) likte the little brother of the R30 but i havent played one so dont quote me on that... plus the oranges have sick master volumes so its cool to have more watts than less me thinks.
both come with v30 speakers(which agree with the oranges very nicely) , both have that warm huge orangey-ness to them that i love.
all that being said....
id seriously think about a head/cab set up as the orange cabs arre
amazeing (id go 2x12 as in my experance the orange 2x12 has just a hair less bass than the 4x12 and is ALOT lighter, there built like tanks...) and you can even use that to make your marshall sound better (

) but thats just me... also if you playing around in a shop that has a few oranges dont pass up the RV50... i know thats not what you were looking for but its one of the nicest amps out there IMHO and worth atleast a try out....
i hope that helps, oranges are rad and good luck on your quest!

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