Benefits are that its easy to pick a slightly different ratio and it gives less of a side loading.

Neither of those things is really any use on a road car IMHO

Straight cut cogs are good for racing when you need a cheap way of changing ratios etc, but i cant see why anyone would want them on the raod unless its a situation where slideloading is excessive on helical gears (mini drop gears for example, or pulsar gearbox where the case can get mullered on a launch)