The only 9500s that mod to 9700s are 256-bit ones (L-shape memory layout.) The 128-bit cards may mod to 9500 Pro. Excelent cards, either way. A bought a 9500 to try to mod to 9700 back when I had a 9500 Pro. Unfortunatly, it was 128-bit, and didn't softmod to 9500 Pro without checkerboarding. I sold it to a friend. The 9500 Pro served me well, I think I was getting 16000 3DMarks with a Barton 2500+. I'd take a 9500 series over 9600 any day (even if it were a 9600 XT.)
I haven't had any experience with GeForce4 Ti cards, though.