I just weighed in at 217 and these are my fixie wheels:
DA low flange 36 3x'd to MA3 (no probs whatsoever, I expect these to last many years)
Phil high 32 3x'd to DeepV (probably the same strength as above wheel)
suzue jr 36 x'd to MA3 (actually, no problems in 3 hard years of messenger and cargo bike work)

I think that:
spoke count has more impact on wheel strength than the label does (within the realm of quality rims, at least);
A properly built and tensioned wheel made from mid range parts will easily outlast a poorly built wheel made from the top of the line parts.