I might be wrong, but I do believe the Ponzol piece would be a little more open of a face than a 5 link.
A 5 isn't very open though, so a more open face and a stiffer reed(you said you use 2.5) may do you some good. A 2.5 is no good at all. Especially for legit playing. For a jazz peice I use 3, but I could see someone using a 2.5 for flexibility. Otherwise, work up to a 3 or 3.5.