Can anyone recommend a decent free sampler for mac?

Hi guys,

I recently downloaded the free Kontakt player bundle which I've been playing around with and has been grand but recently I came across a problem in so far as it won't let me use instruments outside of the ones which come with it.

Or rather it will let me load in other instruments and start using them but then it times out and the midi sound disappears. I've been trying to use the sonatina symphony orchestra (http://sso.mattiaswestlund.net/) with it and I really like some of the sound files in sonatina but it would get pretty difficult if it kept cutting out and from what i can see on the Kontakt free page it won't allow me to use any other outside libraries unless I upgrade to the full contact version which i can't afford at the moment.

I'm very new to using samplers and for the moment I'm limited to only free options so I'm just wondering if anyone could recommend a decent free sampler which will play sfz or sf2 files (like the sonatina library) on a mac?

Thanks!