One would hope the reports of cleaner cameras from later batches are correct. But, I don't think anyone can say that definitively.
If you really want one, I suppose you could buy one, check it immediately for dirt on the sensor, run a few hundred shots through it, and then check again under identical test conditions. If the test shows an unusual amount of additional dust, you can return the camera to the retailer, using the test pics as justification. Be sure to choose a retailer who has a favorable and hassle free return policy.