As a practice we use Iris for everything - accounts production, business tax, personal tax, trust tax, automail, practice management...
We haven't ever really had any major issues with the software as such, but there are a few annoying things like not being able to bulk email from practice management etc. One of the main issues we have had with Iris are their communication on the sales/billing side of things, plus they are pretty expensive!
After a demo with Digita a few years ago, we decided it wasn't for us as the accounts software didn't seem to be as advanced as Iris. However we have recently had a demo and they seem to have ironed out the negative points that we saw a few years back. Plus their pricing is a lot more reasonable than Iris. With an addition of time and fees software there is still a huge cost saving. There seem to be other benefits too, such as their version of OpenSpace being free whereas Iris charge per submission and there is a memory limit.
Has anyone made the switch from Iris to Digita? If so how do they compare and is it worth it?