Hi there - the newer version is a little more streamlined than the classic and incorporates an antibacterial mouthpiece. I bought one for my daughter(she's 14 with CF)and it certainly increased her sputum clearance. The same effect can, however, be achieved by placing a resistor into the inspiratory valve on a PEP mask and we now prefer this as the PEP works the expiratory muscles at the same time. Not particularly a Uk thing in terms of CF although they are recognised as being beneficial to some sufferers(although, as with many treatments, some do not report any obvious benefits) . Definitely worth a bash but we prefer the PEP for the reasons stated.
Good luck and keep well
MumUk xxx