I started using Acuity on their free trial and it worked OK. I then decided that I wanted to try the market but other 'simple' scheduling systems either weren't or just didn't do what I needed them to. Part of Acuity has allowed me to upload registration forms, so I can save on the printing, and help the planet. Another system decided that I should upload forms by a partner group before linking them back in. Why would I want the extra steps and work?
Acuity also has quite a quirky system. Don't look for help buttons but one's that say 'psst. Ask us a question' and other funny little quips that just make the experience more fun, especially when they change on each page refresh.
I also had cause to question part of the system to ensure it did what I needed. Their response was swift and detailed. I have now paid for their basic package for a single business person and am looking forward to really getting to grips with it.
I am UK based and have chosen this company over UK ones.