Yep Sleeper we have two of the Outwell 400's and they are a good Lantern, but this new one using a Single T6 Cree LED at 600 Lumen with 30hrs run time is very interesting.
We have the Cree T6 Magishine Bike lights, that run of a small battery pack, and they are stupidly bright, although run time on full till is just a couple of hours or so.
Hi A900ss, keep an eye out for Aldi/Lidl doing the "D" Cell batteries last time they had them I seem to remember the price being £2.49 for a pack of two.
You can buy Dummy "D" cells which take "AA" or "C" cell batteries, but the run time would be seriousley reduced.
Having said that, always check the Mah of rechargeable batteries, some "D" cells are no better than a good "C" cell in that department.