The BX500 is a great little amp. Nice and clear, 2ohm capable and plenty loud. A compressor is far more useful IMHO that an octaver. Having owned (and still owning) lots of Carvin stuff, I would agree with CL400Peavey: find a better cab used. For what you'd pay for the BR410 new, you can find a used Carvin BRX10.4 which is, IMHO, a vaslty superior cab. The BRX10.2 (2x10) is a big-soundg cab in a small package. But again, it doesn't all have to match.
Carvin 149/5 String 90/Ergo 33/L.O.G. 266/Chi-Love 3/California Bassists 65