Hey BigDan
I agree with dachopper, but at the same time i use a general rule for bow kites and that its they have a general range 2 sizes above and below the actual kite size.
In saying that it doesnt mean that the kite is going to behave its self particularly well when pushed either side of the optimum wind range, but generally will feel heaps safer and more in control than a c kite.
I fly bows but i suggest you have a look at some of the newer Hybrids i think that theyre alot more stable in the air than most of the bows.
Merman