the cable (between the charging block and the tablet) usually isn't an issue, just make sure you use something of decent quality, not a cheap knock-off from eBay.
The charging block itself does make some difference but again as long as you use a decent quality charger you should be fine. Check the small print on the charger for the output, because that's somewhat important.
USB port - this charges at about 500mA (miliamps, or about 1/2 amp). It will charge your tablet if it's turned off. It probably won't be able to charge the battery if you're using the tablet -- best case I can see is it will still drain the battery, but not as fast as if it was unplugged. Some of current from the USB port will offset the battery drain from using the tablet, but it won't be enough to charge the tablet while you're using it
1 amp - some phones came with a 1amp charger, some of the new large-screen phones come with a 2amp charger. Again, turned off this will charge your phone faster then a USB port. It may be enough to charge the tablet under light use, but not if you're really working it. Under hard use I think you'd still loose battery even if it was plugged in, but quite a bit slower then if it was unplugged.
2 amp - probably what your stock charger is. If possible use a 2 amp for best results, unless you can leave your tablet turned off - in which case a USB port will work just fine over night, as will a 1amp charger. Turned on however, I'd recommend using a 1amp charger (if that's all you have) or 2 amp charger (best option)
wow. I didn't think I'd be so long winded! Short story - yes it does matter, somewhat. Depends on if you can leave it turned off for a few hours or not!
Facebook
Twitter
Instagram