Have no idea what airline your with, but if I found myself in a similar situation I would consider several factors.
Would I be more or less senior if I switched airplanes? Would the quality of life based on the current schedules be better or worse? Then of course look at the pay and bases. If your an F/O then I would also ask myself which one I'd make Captain on faster.
Answer the above questions and I'm sure you'll get the answer your looking for.