I also have a small one inch continuous belt sander which I use to true up the ends of the track.
I don't like the Gargrave continuous track skirt that fits into the ties. As to cutting I use this
Proxxon Mini Chop Miter Saw
The track ties just fits the uppermost notch in the clamp. Cuts perfectly vertical with a grinder cut-off wheel. Adjusts for any angle as well.
I currently have gargraves sectional O-42, O-54, and O-63 on my layout, and for all this track, the center rail was cut square with the outer rails.
I have been so please with my gargraves track that when I redo the layout later this year, I will be purchasing gargraves O-72 and O-80 sectional curves.