The $20 knock-off I picked up on Amazon for a Christmas rib roast reads quite accurately based on a calibrated scientific thermometer I compared it to and stabilizes to a reading in about 1-3 seconds. I didn't realize it was a Thermapen knock off, just searched for a meat thermometer for a Christmas rib roast I wanted to turn out perfect (and it did).

The old digital thermometers did the awhile but I think some of the new ones are pretty fast (and accurate).