Depends upon what you're cookin'. If you've got something in the egg like a turkey, or a brisket, or a standing rib roast, or a pork butt that'll be in there for a while, a probe type thermometer with a remote is great to have.
Instant reads, like the Thermapen are more for quick cooking meats like steaks, chops, tenderloin etc...where you want to get a quick read on whether or not the food is cooked to your liking. Perfect for steaks when cooking for a group and they all want different degrees of done-ness.

Get both. They'll both get used.

Cheers,