The only reason this is only 4/5 is because of its efficiency (if that is even fair). It's been a month, and I am very happy so far. I would call this a full-featured inverter because it has an RF (radio frequency) remote power control (on-off), and that means it does not need line-of-sight (unlike common TV remote controllers; those are IR). It has handled the loads I've put on it, the greatest being a 900W clothes washing machine (regular full-size), of which it should be much more capable. I like its cooling fan operation - it only comes on when it's hot, and it is not overbearing. I could not verify the output, but the manual does not mention "pure sine" as so advertised. The included wires with terminal connectors are appreciated. Shipping was timely from Vevor. (I'll mention I added wires across its on-off switch that I connected to a relay so it could used it with a regular 120V wall timer - this is a very minimal modification. This way, a timer can be used to turn it on and off, thus saving your battery from off-use power drain. I use this inverter to run a dehumidifier.) I definitely would not advise against this unit.