Capn I've gotten 8 hrs plus with r44 running 4 chan with still a light or two on the meter....even longer with mp3450.
I'll second T-90's findings. You'll get a lot of runtime for the R-44 using the MP3300 batteries. I can tell you that running 2 channels w/phantom at festivals for the past few years, I was getting at least 12-13 hours with a light or two still glowing on the battery's meter at day's end.
The size m adapt a plug at radio shack is sold out. Any other inexpensive ideas?
With Radioshack going under, you can usually find reasonably priced (for now) Adaptaplug tips on eBay and sometimes on Amazon. Otherwise, if you're handy and careful with a Dremel, saw blade, chisel, needle-nose pliers, etc, you could remove the "skirt" on the Tekkeon tips that keeps you from plugging them into the cable with reverse polarity.