I have the Panasonic 25mm f1.4 and the 42.5mm f1.7. I use the 42.5 mostly for the occasional portrait and for photographing paintings for documentary purposes. I love the look of the 25, but my 15mm f1.7 gets more use. I'm thinking of selling both and getting a Sigma 30mm f1.4 instead. Long enough to replace the 42.5, short enough to replace the 25? Or not?