For me, the way the program looks affects how I interact with it and how I use it.
I have used Reunion for years and I like it very much.
Reunion, RootsMagic, MacFamilyTree have demo versions to try.
Family Tree Maker is another option, but i can't find a link for a demo version.
How easily can you find your way around, add records, attach files, make charts?
How are the help files? Is there online or telephone support?
Commercial software tends to be more maintained and may have better support.
Also consider is the cost of the software over time.
Reunion costs $99.
As the software is revised and new features added, you pay for upgrades-$49.95.
You don't have to upgrade, but it is something to consider when you evaluate your options.
In the time I've owned the software, I've paid for at least 3 upgrades.