Websrv,

If I had the choice, I would use differential encoder outputs but those encoders do cost more. Plenty of us digital, avago, HP/Agilent single ended encoders are being used today just perfectly fine. Just as servo drivers that are only single ended encoder input such as Geckodrive and leadshine. I have about a dozen Gecko320's that's been running for years. Those companies sell thousands of them.

You don't need expensive encoders either. amt/cui encoders work well and under $25. AMS magnetic encoders are even cheaper.

You can always add external differential encoder line drivers if you require them.

The idea here is to get brushless driver/motor technology on a hobbyist budget. A single new tamagawa encoder that you propose cost more than the driver itself. Doesn't matter if you can get Tamagawa encoders and brushless servo motors for cheap. If we can't easily buy them at the same price, what's the point of even mentioning them.