The GCV330 features 2 heat settings plus a turbo fan boost to further speed up heating your room as well as a 24hr timer.
The GCV355 features 2 heat settings plus an adjustable thermostat and a turbo fan boost to further speed up heating your room.
The GSCV270 boasts 3 heat settings, and adjustable thermostat, overheat protection, and a 24hr timer.
The FCV510 has 3 heat settings plus a turbo fan. Top mounted controls, including an adjustable thermostat, very portable.