At the end of the day, the effective defense is whatever you train to use. I think the advantage of spray is that it’s like a shotgun - less training needed.
But avoidance is the key. I often bow hunt without either. Also I don’t try to feed them sandwiches and take pictures with cute little...
What matters is having a rigid frame, the ability to tie meat tight to the pack (you do NOT want it to shift while you are walking) and the ability to put weight high over your center of gravity.
Get a rope and a sackful of heavy stuff and try it out with your pack.
My standard training for solo hunts: pick a trail with an uphill grade for several miles. Run uphill at a jogging pace. If you’re hunting deer, see how far you can run with stopping and that’s the maximum distance you should hunt from the truck. If you’re hunting elk, run uphill and walk back 6...
Agreed that crispi isn’t what you’re looking for. With that said, they just came out with a new Valdrez so the old version is on sale at a number of places. Pick up a pair at half price and see if you like the brand in general.