Loaded a split so big tonight I had trouble getting it into the stove without banging the tubes. Big chunk of three year plus dry old Elm. That one split burned for over 3.5 hours at 600. More biguns are going to get made this summer!
I discovered this a while back. There are a lot of logs in my shed that I didnt bother splitting when I cut my last load. I do like having smaller pieces around to help get things going and to fill up the corners. If Ive got a good coal bed in there, I go with 'if itll fit through the door, its already small enough'. Keep one thing in mind though. The stuff Im burning was dead and dry standing spruce and pine. If youre cutting live wood and want it to dry, at least bust it in half. Birch will sometimes rot before it dries if you dont split it.
If I get something that dries easily I am going to make a few biguns... Ash for sure, box elder dries easy and normally burns up in a flash, so might make for a decent big split
I always make a good amount of big splits for overnight fire holding. My wife won't load those in the fire, but I don't expect her to. She likes the smaller splits. Those large splits do require small splits or sticks to stuff the stove full.
I like have a few "Night Blocks" on hand for when extended burn times are required. Some 6-8" whole rounds or a 12-14" rounds once split added to a good coal bed and you'll be waking up to a good bed of coals several hours later.