Karolh,
I think you should consider yourself pretty lucky. You added almost a pound and a half of weight(assuming it is an unmodified G-23) to an airplane that is probably in the 9 to 11 pound range I'm assuming from the wingspan? For it to have retained it's good flying characteristics is suprising. Do you have to come in a little hotter than with the .90? I have a G-90 in a WM Midget Mustang. Although it runs reliably it is not a powerhouse in it's class. That was my first and last ST engine. Glad to hear you had success with that combo but I think in that size plane your positive results are in the minority.

marty