I have an Innova longarm on a frame and have always been able to get questions answered by phone. Innova offers 24/7 phone assistance, so there has been no need to have a dealer nearby.
You could call Innova or an Innova dealer and ask about the differences between the machines. I wasn't aware of any changes in foot controls, but I haven't actually looked at the sitdown machines. The Innova web site seems to still show 3.