I am a big fan of autoformer volume controls and have been listening to the ones from Intact Audio for many years. Screw pots is all I gotta say. Dave Slagle's AVC products are available in many configurations and also custom work is available.
What do you want from an autoformer? I can safely say you can find it at Intact Audio. Lets look at a few of what is available today.
The top of the line is a 47 position stereo attenuator that goes seamlessly from +5dB to -51.25dB in 47 1.25dB steps. This stereo unit can also be wired as a mono balanced unit. It is also available in silver if that is your fetish.
I know I'll be picking up one of these at some point for a DHT preamp. Two of the 23 position autoformers are placed on a single board with a "penalty free" balance control between them. Each autoformer step is 2.5dB and the balance control allows for a 1.25dB shift to the left or right. Maximum attenuation is 52.5dB.
This is what I'll be installing in my Brook 12A monoblocks I'm working on. This is a compact 23 step autoformer. I'm going with the stock attenuation with the following steps 0, -3, -6, -9, -12, -14, -16, -18, -20, -22, -24, -26, -28, -30, -32, -34, -36, -39, -42, -45, -48, -52 and Mute. Since this is Intact Audio Dave will wind any taper desired