Let's face it - TV set resolution is 360x480 visible (525 total lines). No more no less. (PAL is 360x576.) So anything above 640x480 you feed into a TV-out circuitry is going to be intermangled down to the 480 line format and 5 MHz pixel bandwidth that this standard allows.
Radeon cards have good signal quality, and very tweakable image position, size and sharpness (that on SVideo only).