What is the difference between W6 and W8 AT?

The W8 variant is a feature-loaded variant in comparison to the W6 variant of the car. Moreover, if you are one on the person who drives the car mostly in the city rather than frequent highway travels, the automatic transmission is more preferable. You may go for the manual if you are one of the frequent highway travelers. You may check out the detailed comparison in the given link by selecting a filter of the required variants.

Between the AMT variant of W8 and W6, primary difference is in the looks (alloy wheels, chrome, etc). There is an option to add fog lamps even in the W6 variant as accessories so its not a problem. No shiny DRLs or projector headlamps though. As for wheels, you can get those replaced with alloys if you want to. The cruise control isnt very important in cars with AT so its not a big deal.