Personally, I like the Hartland rails a bit more than the Aristocraft model. It's smaller and looks more better with other large scale stock. If you decide on any rails and your search leads you toward the Hartland, don't confuse it with the Delton Doozie. The Delton Doozie is the basis for the Hartland model. When Delton went out of business, Hartland obtained their tooling and reissued the rails under the Hartland name. The motor block was redesigned and is much improved over the earlier Delton design. The Delton motor block has only one powered axle as opposed to the Hartland which has both axles powered.
If you find a Delton Doozie you can contact Hartland and they will sell you a motor block with instructions on how to do the switch. The fellow I spoke to at Hartland, when I did one a few years ago, was very helpful.