Seconding Herpstats 100%
Jumpstarts are a great starter thermostat but keep in mind they will not be as accurate as a proportional thermostat like Herpstats. Jumpstart is an on/off style of thermostat meaning it can only go from 0% to 100% full power, instead of gradually like portional ones. It's also worth mentioning they have a shorter lifespan, unfortunately they are prone to needing to be replaced within a year or so.
However if you are in a tight budget the Jumpstart is a good placeholder until you can upgrade to a Herpstat. I PROMISE the lifespan and reliability of a Herpstat is sooooo worth the upfront cost! Plus they look snazzy!