You're right, the regular stuff may regrow some hair but it is terrible for overall scalp health!
I've been using the new foam for a couple of weeks now and haven't experienced any irritation from it. I've never used the regular dr. lee's minoxidil so I don't know how it compares.
The only issue you might have with the foam is application - it's a little harder if you have long hair. I have short hair at the moment and it is very nice!