I love the .218 Bee, specifically the .218 Mashburn Bee. I have a twenty-four inch Bullberry barrel for a Contender. Lots of fun.
The only issue is getting dies and brass for it. My dies came from Bullberry as the Mashburn Bee chamber has some variance from maker to maker. Brass came in the form of loaded ammo from MidwayUSA, so fifty pieces of brass ran me $75.00. Winchester only seems to make runs of Bee brass occasionally, so I need to keep an eye out. Even then, the brass is $35 per 100 pieces.
Luckily, I also have a K-Hornet barrel with a 1:12 twist rate. Brass is much easier to find and much less expensive. The only issue is the K-Hornet barrel is thirteen inches long, so no butt stock on the Contender with this barrel. Lil'Gun seems to be the powder for the K-Hornet. I have been experimenting with the Hornady 45-grain spire point at about 2000 fps as my .22 WMR load.