Hey EC,
What specific Boogie sound/tone are you after?
For that immediate response brutalz Recto sound the Mod3.1 and Mod3.666 will get you there.
The Recto preamp circuitry is just a slight alteration from Mike Soladno's infamous SLO...same as the Peavey 5150...all more or less the same typology.
The Boogie Mark (MkIIC+, MkIII, MkIV, MkV) is a completely different animal. These use a heavily altered Fender typo preamp stage where the tone controls are located within the preamp gain-stages and have a direct influence on the type and amount of gain an heavily interact with each other. These amps also most often come with the infamous 5band EQ.
As Others have said...for the Recto get the 3.1 or 3.666, for the Mk sound get either a Triaxis, a Studio Pre, a Quad or one of the heads. A simple eq or even one of the Mesa Pedals won't get you there...with the Mesa Boogie Flux 5 being the only one that could get you in that direction
I'm just the opposite of Rich and MJMP.....Mk lover through and through. Can't wait to get my Boogie JP2C