I recently changed from a windows PC to a Mac and have tried various Mac genealogy programs over the last few days. The ones I ended up going back over a few times were:
Reunion, MacFamilyTree, Heredis and iFamily for Tiger. My thoughts? Well, I need something that I am comfortable with, something that gives the same or similar reports that I was used to with Family Tree Maker for windows version 16.
MacFamilyTree - I don't like it. Not user friendly to me and reading some reviews from people they've had problems importing their gedcoms. But I just didn't like it and it didn't seem to do as much as I require.
Heredis - not bad, it's an improvement over MacFamilyTree but it doesn't ooh and ahh me. (it has to grab me).
iFamily for Tiger - it didn't impress me.
Reunion 9 - the way it comes was okay but after playing around and changing a lot of defaults the way it looks and how the reports come out, I like it. But I did have to reconfigure it a lot to get it the way I like it.
No one can really tell anyone else which program is the best to use because it is all really personal experience - what one person loves, another might dislike and find it not friendly to use and vice versa.
The best thing to do it is go to each product's website and download their demo/trial version and try it out to see which works for you best.