As stated previously, chocolate tempering is a tricky undertaking (it’s also fun and delicious, no matter what the results). Good gear vastly improves your chances of success. While the microwave is without a doubt the best tool for melting chocolate, you need a good double-boiler if you want to tackle tempering. Concerning measurement, you’ll want a good digital thermometer. Luckily, there are quite a few reasonably-priced options out there. Probe-style thermometers tend to be pretty good, but I find their reaction times are a little slow for a precision sport like tempering. Instant reads tend to do better in that regard.
If you really want to get serious, pick up one of these bad boys which are not only hyper-accurate, they give a reading in under a second. At $85 they are not reasonably priced. But I use mine for everything from chocolate to chicken. I wouldn’t be without it. Is it unseemly for a man to love a piece of measuring equipment? Maybe. But as Woody Allen once said: “The heart wants what it wants”.