Thanks everyone! Just used the old trusty Taylor clip on thermometer (no probe, no digital read out, or beep alerting me to my desired temperature) and as long as I'm willing to stand there for the last 30 minutes, that one seems to be most accurate.

here are some reviews. http://homecooking.about.com/od/kitchenequipmentreviews/tp/candythermom.htm

Thank you!

Also, I have a thermapen and I just did a marathon batch of donuts and found the polder probe thermometer I mentioned to be extremely well calibrated (i.e. within a degree F)

I have a Polder probe thermometer for roasting. However, it comes with a clip that allows you to use it for deep frying and candy. It was about 20 bucks. Similar to this one

http://www.amazon.com/Polder-Cooking-Timer%252fThermometer-Bonus-Clip/dp/B000S12U0O/ref=sr_1_4?ie=UTF8&qid=1287449087&sr=8-4

I love the combo deep fry / candy thermometer Mr T picked up for me at Sur La Table for under $15 not too long ago (after I broke my old one by dropping it onto our super hard kitchen floor). It has a nice long, angled clip on it. Very well designed. ;o)