I am positive that the PS pump has more parasitic drag on the engine. The vacuum pump is driven by the chain which runs the vacuum pump off a cam like fitting. I don't think it takes as much mojo to spin that cam which hits the back of the vacuum pump. I already sourced the premo solution to having vacuum, e.g., I got a very nice foam padded encased electric pump which goes in the spare wheel well. It looks new to me. I am thinking I can tee into the vacuum resevoir from the trunk area and that way, I can tuck all vacuum lines under the dash vs. the engine bay except the sole one which runs to the IP. I have been screwing around with the manual brakes concept for a while. The vacuum pump (electric) is Mercedes. Actually, all upgrades and modifications are generally mercedes' items except the electric water pump and altenator. I like keeping the parts and components all Mercedes unless I have zero options. I looked at numerous "exoctic" - really hi-end performance cars and actually many have manual steering and manual brakes. I love my manual steering. It is much more responsive and unless one is at a complete dead stop, the turning is almost just like PS until you hit 20 mph, and then it is significantly better IMO.