Too much of a differential (on and off timing) on practically any "every day" thermostat, none are good for incubating. Some stats may be used for a brooder, but incubating has to be more consistent/precise. Do as jimmurray mentioned and get a wafer thermostat, it's the most inexpensive way to go and most reliable. Get an extra wafer for a backup while you're at it, they are only a few bucks. Take a look at cutlersupply.com for them. Some feed stores may have them in stock.
The best I can do is 101.8 before it cuts off and it does't cut back on until 95.7. Is this going to prevent me from hatching any eggs?
More than likely.