I've been trying to choose between the three accounting software. However, I can't decide which one should I use. In terms of user interface, I would go for PeachTree and QuickBooks. MYOB seems too old IMHO. In terms of using for software development, I would go for QuickBooks because I think there are many developers using it and the SDK can be easily downloaded. Also, do these software support currencies aside from dollar? What SDK is easy to use for .NET development? TIA.
QuickBooks is very mature and much, much more popular than either other system. It's also much easier to find an accountant familiar with QuickBooks than it is to find an accountant familiar with either of the two others.
As far as development goes, QuickBooks has a reasonably strong developer community behind it, and integration/the SDK is pretty flexible. There is an official QuickBooks SDK that's pretty easy to use and is downloadable from Intuit's site. The forums are also a good resource: