I have a 4:3 tube (no, really) which I normally use in 1280x960, although Windows will drive it at up to 2048x1536 (if I don't mind having my eyes burned out by 60Hz headache-o-vision ).
When I start Tolva, it comes up in 1280x960 (hooray) but it's not clear this is quite working correctly. When I scan something with magnified vision, the scan data is partly cut off on the right-hand side. Every other UI element seems to be correctly positioned, so perhaps this is just an afterthought?
However, the video resolution menu contains the following choices: 1280x720, 1680x1050, 1920x1080, 1920x1200. I've read both that the game only shows 16:9 and 16:10 by default and that it tries to show what you've actually got, so I'm not sure if that's expected.
If I select 1280x720 it goes into a letterboxed mode. If I select one of the higher resolutions it stays in 1280x960. If I first increase the desktop resolution it will letterbox one of the higher resolutions. This all seems to be working much as one might hope except inasmuch as I don't know why the desktop resolution restricts it.
If I start the game with -allowunsupportedaspect, it adds to this list 720x480, only. This is a 3:2 aspect ratio and definitely not what I expected that argument to do.
Having switched into one of the letterboxed resolutions, I can only get back by editing VideoConfigurationData.xml.
The scan data thing is the only thing that (fairly insignificantly) impacts my gameplay but it seems in general this is not what I would expect the game to do on a machine with a 4:3 display, and as I understand it 4:3 is intended to be supported.
 Unlike on an LCD, 60Hz on a tube gives a flicker which some people find extremely unpleasant.