Clamp meters are handy to have around a RV. Just realize though that the accuracy is around +/- 2.5%, which is nowhere near as accurate as a standard meter, but still close enough when chasing down parasitic loads and such.
This is the one I have:
http://www.amazon.com/Precision-316-...ords=B%26K+316
I recommend it or it's similar competition as it is intended for low current applications, whereas the less expensive ones you find at Lowes, etc. are designed for higher current household and commercial applications, so they won't have the same resolution.