Omnifocus is a great app to use if you have a lot of stuff to keep track of and you subscribe, in some form or another, to David Allen's GTD system. For simple reminder management where you just need a list of things to do without any sort of hierarchy, Omnifocus is going to be a bit overkill for your needs. If you have multiple layers of activity that needs to be done (work, home and then sub-trees off of that) and you are good about actively using OF as a tool, then it is a great investment and can become something that can help you stop overloading your brain by trying to remember every little detail about every little thing that needs to be done in your life. Tracking both the personal and professional parts of your life in the program is vital. Without doing both you have only a half implemented system and you won't get a ton out of the program if you sub-sect your life like that.
My suggestion,, do a little reading on the program online and watch some videos (
David Sparks' stuff would be a great place to start even though they are all about an older version of Omnifocus) and then once you have a basis of understanding about the program download the free trial from Omnigroup's website. Omnifocus is a fairly complex program, so as long as you go into it knowing that and have an open mind you should be fine.