accuracy on temp is a relative term, if you put a temp probe in a bucket, you can manually adjust the heater to the correct temp, reguardless of what the dial says. I have a all-glass heater that is tough as nails but to get it to 81 deg I have to set it at 72 deg. but once set properly it holds an accurate temp like a champ. what I am saying is get one that wont break. double the price is nothing if you buy three a year to replace broken ones.