Generally I use to prefer Flat CRTs until I got a PVM and noticed how much better the geometry was. However, I thought that was merely just because it was a PVM, but then I looked at plenty of other curved CRTs spanning over a year and I think I'm starting to prefer the curved variety as apposed to the flat ones. I've owned many HD flat CRTs, and non flat crts in-general. They tend to, including the Sony Trinitrons, have bad geometry and other issues where the image is tilted slightly, corners are messed up, (not referring to colors which can be repaired via deguassing ring) and generally poorer color quality. From what I can guess is the technology was never truly perfected since they were out only a few years and they use a different "tube" or something. I'm aware of the Sony KD-34XBR960, which is said to be and has the hardware to boast it, to be the best consumer HD CRT that was on the market. I've never seen it in person, but I've heard issues with that one as well although generally praise. Now I haven't owned a Sony HD CRT before as they are rare, but I've owned Toshiba, Phillips, Samsung HD CRTs, and even seen Panasonic and generally they have this issue. So it seems to me that curved are better as they have less issues compared to the flat ones and are more readily accessible. What do you prefer?
flat HD tubes are useless, light guns shouldn't work on them from what I understand (not that I'm a light gun guy).. I doubt the flybacks in them are any better too, usually when a product is towards the end of its commercial life (meaning CRT's where becoming old tech), corners tend to get cut. Sounds a bit tin hat theory but look at PS2 and PS3 super slims (the last of both systems) horrid construction.. What annoys me is when people throw out crts (put them on the curb for pickup) some knob heads, the guys who scrap stuff thinking they'll get rich off it or something, smash them open to steal the copper and leave a huge mess (which the council won't touch).. /rant
The slim PS2's and the Super slim PS3's may have cheap build quality compared to the originals, but they are by far the most reliable.
My personal bias is towards the old Triniton tubes (the original vertically flat, horizontally curved ones - not 'FD Triniton'). Being aperture grill tubes, they have much simpler convergence circuits than shadow mask tubes do and require very little added electronics to keep the screen linear. Having said that, a properly adjusted shadow mask tube can give you a really excellent picture, but require regular adjustment or the image quality will degrade. The biggest problem with flat CRTs is the same as the problem with wide deflection angle CRTs - the length of the electron beam changes significantly depending on the current scan position on the screen - it's shortest when the beam is in the center of the screen, and gets longer as the beam is deflected to the edges of the tube (either up/down or left/right) - the deflection is also quite non-linear, and the further from the center of the screen you get more drive you need to move the spot the same distance on the CRT surface. In practice, this means that you have to generate specially distorted vertical and horizontal drive signals and modulate the focus and intensity settings on the tube so that the image remains in focus and of constant intensity over the entire screen - in practice the TV firmware is normally given some average values for these correction terms, and maybe there are some service mode adjustments to trim them, or maybe not. In any case, it's very unlikely that your specific mass-produced CRT is going to respond exactly the same way that the firmware is expecting it to. The other thing to watch for is that a lot of flat screen CRTs were HD capable, and in many cases didn't like running at a 15KHz line rate - so they didn't. instead they were run in scan-doubled mode at 31Khz and 120Hz frame rate. This breaks light guns (if you care about this) and also introduces a 0.5 to 1 frame delay into the video. The ones that attempted to do motion compensation introduced even larger delays.
I have a flat non-HD CRT and my light gun games work fine on it. Maybe it's because I'm using the Saturn and PSX and not like the Xbox.
