Does it take longer that way? I bought my NATPC from Electroniceze as Wendy Lou had run out (Now she's got more and I only received mine today so I'm wishing I hadn't been so quick off the mark) and the connector for the power charger is too small for the DC-5V slot. It looks like a Nokia phone charger and keeps falling out and won't work with it. I'm charging with the usb lead but that means my one usb slot will be occupied everytime that I need to charge. I've sent a complaint but who knows how long it will take before they do something about it. I've not seen any reviews from Electoniceze whereas I've seen loads of good ones about Wendy Lou.
Charging by USB doesn't seem to take any lomger than the mains charger, but then again I don't usually sit and watch it. It does of course take longer if you use the device at the same time! I guess from flat to full in a couple of hours.
As far as I understand it, the M009S comes in two versions - a 9 volt and 5 volt. The one I recently purchased from Amazon is the 5 volt model and the replacement chargers currently sold on Amazon seem to be for the 9 volt model and don't fit... There doesn't seem to be an easy source of spare 5 volt chargers in UK yet... (I like to have one at home, one in the office) USB charging works just fine - straight from USB socket on PC - but can I also use a charger direct into the USB on the tablet - I have an old phone one of the right size... Dare not try as I don't want to damage the tablet....
I used my usb lead and a usb plug, charger. I have to add the Electroniceze sent me another charger really quickly. If you haven't sorted out your charger problem yet, I would ask one of the people that sell the M009S eg. Wendy Lou or Electroniceze. If they can send me a replacement charger that quickly, maybe they can sell you one. Worth asking the question.
Just a word of warning to anyone who likes to flash non-standard roms (people who stick with the supplied firmware or the LY official updates needn't bother reading this).
Some of the thrid-party firmware downloads for this tablet, and the 8Gb version, re-program the USB port in a way that affects its charging behaviour. The result is that some USB chargers won't charge at all, and others charge only at data-port rates, much slower than a proper charger, and often more slowly than the battery depletes when the tab is working hard. So anyone who finds this happening after they've installed third-party firmware should look to that as the cause before blaming their charger.