I'm on my second one of these. The first had to go back after the inverter stopped working. Not too sure why as I've ever only used it with an appliance that draws around 10W. I think the inverter is the weak link in an otherwise good product.
Battery seems to last for ever, hardly surprising with 40A at hand, most of the cheap and nasty ones use 12A or 17A batteries which are also probably cheap and nasty.
Inverter, 300W which is fine for a fair amount of small appliances, old style lighting, laptops etc.
Jump Leads, nice and chunky, a bit short which means the power pack probably can't stay on the floor, short leads mean less power loss for jump starting which is exactly what you want. Also there's a switch and cut out which should make it idiot proof.
It's jump started my 5 cylinder diesel with no problem and I hadn't a clue when it was previously charged
Inverter, it generates a modified wave form which is fine for resistive loads such as old style lighting (tungsten/krypton,halogen), also runs laptop power supplies. This will be useless for inductive loads such as fluorescent lights or energy saving lights. It's a simple inverter for simple loads. It powered my laptop and other small loads with no problem for hours on end, but don't expect it to power fluorescent lighting and some motors. If the inverter screams then you've plugged in an inductive load. a good inverter, that handles such loads, will cost several hundred pounds alone.
a/c 500mAH adapter woefully small. Ring recommend 36 hours charge, but at 1/2 an amp maximum and a 40AH battery capacity it doesn't take much working out. 36 hours may be fine if you've just jump started a vehicle, but if the battery has been run down with the inverter, 12v output or lamp then you'll be looking at 4-5 days charge. I suppose there's no chance of over-charging with 500mAH
I don't regret buying this and I would buy one again as there isn't anything else out there. It's fantastic for jump starting and good for small mains voltage loads. I think the best way of charging is via the cigarette socket if you know you'll be on a 3-4 hour journey, unfortunately there's no indication of charge via this method. Don't expect to be able to run mains 230v inductive loads such as fluorescent lighting, I've known cheap 1000W petrol sinewave generators fall over with just two 40W fluorescent tubes, but handle two 500W floodlights - it's all down to the quality of the inverter and this power pack has a bog standard cheap one to keep within budget.