I'd rather gamble on West's head than Stackhouse's body.
If Stack's body doesn't hold up you simply have an old player who is still a decent contributor, basically exactly what happend with Finley last year. He didn't give us what we expected but he could step on the floor and not kill us at least.
If West's head goes wrong? Well who knows the possibilities, but it's possible it tears up some of the team chemistry. Not saying it's true, who knows exactly, but imagine if that Gloria James rumor is true... that kind of damage to your team chemistry.
I'll take Stack every day. Plus Stack actually is a SF, West is a redundant combo guard who does not address our needs.
Stack is a solid player and can still score. He impressed me with the Bucks last year, still playing well and in the Playoffs too. If we don't have a better option I would prefer him of all the available guys. He'd be strong in a reserve role.