Good APS-C sensor can be better than a full frame as it gives impression your lens are longer (multiply by 1.6). In plane spotting it is an advantage as really long lens are expensive.
Quality lens e.g. L's series by Canon are advantage.
However I don't agree with statements regarding tripod. Actually I invested in Sachtler fluid head tripod which costs more than my 7D and I can say that panning action cannot by compared to cheap ones or holding long lens in the hands.
Just try it once and you will see.