Use the 12 ounces, as you get 3 mags (7 round) easily, and then connect to your remote line. The tipx holds a charge when you connect your remote line, so you could literally connect it to charge it, then disconnect it, then shoot a mag with it disconnected, then connect it again when you reload the next mag, and repeat. I found I was getting 6 good shots with mine disconnected, but I haven't chrono'd it to see what the drop off is...
That way you don't add any extra weight, and you can still use it without the remote line. Unless you just don't want to worry about air, or get in a sticky situation, you can just leave it connected to your remote line.
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