Jimmie,
No downside at all.
If it wasn't for double entry, I would still use Allscripts. Its features are significantly better than NewCrop. When I need to know what forms of a drug are available, I always check Allscripts, all of the information comes up with the drug name. It allows you to save both a local and a mail away pharmacy. It is web based, nothing to store, nothing to back up, always accessible anywhere I have an internet connection. I actually still let the refill requests come into Allscripts, it is much easier than the routine in AC. You can prescribe from multiple software, but can only receive refill requests via one.
I had a hard time switching to the AC prescriber because Allscripts was so much better, and so much more reliable. But, alas, I have grieved and moved on.....