Originally Posted by chaosgow
Check out the PDI03. Not toooo expensive and does the job well
Yes. Or a box from Two Notes (Torpedo).
Mind that you will blow your amp, if you run it without any load on it's speaker outputs!!!! If you don't connect a cabinet to the speaker outputs, you have to have some kind of load box, like the Palmer PDI-03 or PGA-04 or the Two Notes Torpedo (not the Torpedo CAB, though).
Another option to record direct is to skip the power amp completely and go directly out of what usually goes into your 20/20 into your audio interface. Then use some convolution plugin to do the cabinet emulation (LePou LeCab, Kefir, Recabinet, Mellowmuse IR1A, Redwirez mixIR2, ...) using cabinet IR-files. This will bypass the poweramp stage at all, so you don't get any poweramp tone here.
EDIT: I just saw that the 20/20 has attenuated line outputs, but I am not sure what those bring to the table, because if you'll use them, you will need cabinets hooked up to the amp or a load box. Hooking up a cab defeats the purpose of direct recording and the load box will give you line outs as well...