I haven't heard of Riverside, are they Scottish or, as the price suggests, in the US? I would expect schools which offer the cheaply priced packages to offer the basic no-frills PPL on the basic no-frills PPL aircraft, most likely using hour builder instructors who are not usually aerobatic specialists and may have no interest in or experience of aeros. This is not meant to be a dig at those schools or their instructors (if you haven't yet done so, you could search this forum for the endless debates about package vs pay as you go, UK v US etc), just an observation about the product which they are selling. If, by coincidence, the school you choose happens to have an aeros nut on the staff and a suitably upside downy aeroplane, then you're in luck. Otherwise, you might have to wait until you 've obtained the PPL and then seek out a suitable instructor and aircraft.
PS: on a separate note, check very carefully what is and isn't included in the package price. Read the small print before you sign up.