I bought Daylite (productivity suite) 2 years ago. after a year of headaches I finally gave up and went back to using iCal etc to run my business. Why? Because I found I was spending so much of my time trouble-shooting problems in Daylite that any productivity savings the software might bring were more than wiped out by down-time.
With the arrival of Daylite touch I thought I would give Daylite another try. So I downloaded the latest 3.9.1 version and... Same old Daylite - Nearly two days on I have yet to get Daylite to successfully sync with just one user and minimal address book data. (Others are having the same problems, and I've done everything I can to resolve them on the forums) - It's painfully slow and buggy and frustrating - It just doesn't work reliably enough to be a viable option for me.
So I have just deleted it, and will put my $150 loss down to experience.
I've nothing against the guys at Market circle, quite the opposite, I also own the latest version of their Billings software which I cannot recommend highly enough - it's a joy to use. I just wish Daylite was. I suppose it is just trying to do too much?

Think really carefully about the impact possible troubleshooting problems with this software will have on your time and productivity before you buy.