Those desktop printer decals are alright but the thing is that no matter what the package may say, they are not very waterproof at all and are best kept indoors. If you're planning to print out a few of those and put them on your car, they'll start fading REAL QUICK or the ink will run off in the rain after a few months, unlike a nice screen-printed vinyl sticker which might very well last forever. Although you could try to coat them with an archival waterproofing spray when they're done.
Don't hold me to this but I think the difference between laser & inkjet ( other than price
) is how the ink saturates the paper. You still might be able to print on those inkjet labels with a laser printer, but it'll probably take a long time to dry so leave them alone for an hour or two when they're done. That's been my experience but i'm no expert. Where's MLE? Zako? Why do I bother?