I have some new found interest in this new 17 now. Bullberry's site states they will be chambering contender barrels in it when ammo becomes available. I currently have 2 rimfire contender rifle barrels. A 17 HM2, which is my favorite squirrel caliber. It works better for squirrels IMO than the 22 long rifle, and almost as well as a 32 long. I would still like the 25 rimfire reintroduced though.
My other barrel is the previously mentioned 5mm Remington. The new centurion ammo works quite well in my barrel, and I enjoy it very much. Seems to be a nice middle ground between the 17 and 22 centerfires. But the thing I like most about it is the 5mm Craig. It is a centerfire version of the 5mm, and can be fired from an unaltered chamber. I will be setting up to reload it sometime in the future, and if I can find someone to cut a mold for me, I will cast for it.
If this new 17 Winchester has the possibility of someone converting some kind of brass to work in it so it can be used as a centerfire, I'll be all in. The 17 hornet may be more practical, but the possibility of using either rimfire or centerfire ammo interests me and is why I keep the 5mm barrel. Years ago when they were first introduced I really wanted a 17 and 22 CCM. Those little cases just catch my interest. But add the ability to use both kinds of ammo just makes it more interesting. A centerfire type conversion may or may not be forthcoming, but I bet some enterprising individual makes it work. I know I will be watching and waiting.