It's ok, but ...
Firstly, this is not a 750w/1000w as per the product description, it is actually 750w/1500w so do be careful on campsites with 5-6amp supplies and even on 10amp supplies if you have a few other things running.
The description doesnt mention that the fan has to be running all the time. It gives the impression of 2 heat settings plus a fan for cooling air. That's not strictly true.
The fan is on all the time, you then choose either no heat or 1 of the 2 heat settings. This means that the heater is quite noisy. It also means that as cooler air is brought into the unit and blown across the heating elements, it doesnt heat very quickly. In fact, it seems to put out less heat than the Quest Quartz Slimline 400w/800w which is half the price and runs completely silently.
Also, when just on fan for cooling - well it's completely useless. You would be better off with a cheap desk fan. It has an oscillate function which sounds like a great idea, but with the fan being so useless there really is no difference in the overall heat/cooling whether or not you use this function.
On the plus side, it is tiny so doesnt take up much room in the vehicle. Like it's cheaper brother, it has a safety switch on the bottom which will cut the power if it tips over.
All in all - it works, but you can get better, quieter heaters which use less electricity, and for less money.