any 'custom' wheel will be stronger than one you buy from ebay. handbuilt wheels are always stronger than machine mades. for the most part, bike prices are transparent: you get what you pay for.
for a cheap strong wheel you should consider lacing and definitely have it built locally. counter to what i just said about spoke length, a 4x wheel on any rim would be very strong. if the arguement for deep-vs strength is based in interweb blowout prices, than i am trading camps and saying that deep-v rims don't mean dick. anything handbuilt is stronger.
the mavic cxp33 is a nicer aero rim, and not much more expensive.