Yeah you can also get cheap but still decent chargers on amazon, they are off brand, but as long as they are somewhere between dirt cheap and basically the same price as the ones from Apple, you should be okay if the reviews look good and legit.
I've done that before my self like three times now. No fucking way I'm paying 100 bucks for a god damn laptop charger.
And point taken about the field size.
I would prefer a prerecorded voice my self, since if you have your speech off, you'd need to turn it on and then use that key while not picking up any more items, then turn it off again. That's kinda hard in the thick of things. Plus, by the time things get quiet enough to understand it, you may have picked up another item again.
Have you considered using a system more like the older games, troop2, super deekout ETC, where you can use items you've picked up when ever you want? That way you can use them more effectively... You could use the number row, letters, or page up and down or something with the item name voiced as you scroll to it.
Maybe this would take too much out of the randomness though I don't know, but at least then you could choose when to use things like super speed and possession.