Another big issue is whether your monitor is passive or powered. Alot of venues have passive monitors... so turning up with a powered monitor could be a bit of an issue. So to get around this you are looking at getting a passive monitor and a separate power amp should you need it... like a bass amp and a bass cab. The FRFR story thread will give you some ideas... but ultimately, you still need to have some knowledge of what you are dealing with. A monitor that you can use as a bass amp and put the rest of the band through... well, for me, that's preferable, you've just got to sort out what your real requirements are.