RE: Bionic Buck or Mckenzie
JimBow........I have both myself, and if you are talking the bulk of your practice being with field points? There IMO is absolutely no comparison as to which is better.......the Bionic Buck is a dream to practice with.
Not quite as lifelike up close I'll concede that, but it takes some MAJOR abuse, and arrows pull out as easy as a bag target but it's much tougher than any bag target. I have been shooting mine for 3 seasons now and it looks like I've shot it for a week. Arrow still only go in a few inches even in the small kill circle.
I would venture to guess that it will hold up many many times longer than any foam 3D target. I couldn't tell you how much longer because I'm not even close to wearing out a single midsection.
The McKenzie collects dust and an occaisional broadhead and that's it.
As for weather? I don't know but I would guess you should cover it and keep it dry, it's cloth and material that would get funky if left to the elements.
I haul mine in and out of my basement each session.