Best word expander - NeeCee

I'm looking for a word expander that really works well with the way I want to type.  I want a word expander that expands with any trigger, i.e, space bar, apostrophe, parenthesis, period, comma, etc.

I also want an expander that allows me to build on an existing word without creating an inappropriate word.  For instance, my shortcut for lymphocytes is ly.  When the VR text gives my essential, and I want to turn it into essentially, I want to be able to add the ly to the end of the word and space or whatever afterwards without creating the word "essentiallymphocytes." 

I was able to do that with AutoCorrect at my previous job, but I now work for another company where I buy my own word expander.  I don't mind doing that.  I just want one that works the way I want it to.  I am currently using ShortCuts and ShortHand, which give me the problem of creating inappropriate word because I cannot build on an existing word.

Can anyone give me a suggestion as to which one would be good to try?  I would appreciate any and all input.

Thank you.