The Audi Rs4 & Rs6 Avant

How come they never made a saloon version of these Rs models? Usually its a sedan/hatch version first and then a wagon

Simply due to popularity. And Audis argument was that the S/RS5 would deal with those not wanting and estate car.

I personally think in part it has alot to do with the S models for example take an S4/S5 with the 3.0 supercharged. A tune, supercharger pulley and exhaust will take you beyond the power of the RS model for Around £2500/$4000 and then another few hundred to few thousand on suspension and brakes depending on preferences and you have something that will out run an RS for a lot less money!!