I'd love to have a Scottoiler on my Baggy, but it's a few items down on the list (after fixing the carb woes, setting up driving lights, and finding a long distance seat solution). However, without the cool automatic oiler, using motor oil or atf aren't really that practical.
I've found that the best product for manually oiling the chain is DuPont Teflon Multi-Use Lubricant. Basically, it's Teflon suspended in a quick-evaporating solution. It penetrates easily, so the lubricant gets deep into the chain, and then dries to a waxy state that doesn't collect dirt.
http://www2.dupont.com/Consumer_Lubricants/en_US/products/dryfilm.htmlBTW, I'm not in any way affiliated with DuPont or any seller of this stuff. I'm just a convert. In fact, I know that this is a solution that's been known to bicyclists for years (not necessarily the Teflon lubricant, but the other wax-in-evaporating-solution-type). I didn't learn about it until I read this in Motorcycle Consumer News (a very trusted source for moto product testing):
http://www2.dupont.com/Products_and_Services/en_AU/assets/downloads/dcse%20msds/teflon%20lubes/Article%20-%20Motorcyle%20Consumer%20News%20-%20Multi-Use%205-05.pdfAlso, note that WD40 is great for cleaning the chain, but doesn't stick around so much as a lubricant (tends to evaporate). I clean the chain thoroughly w/WD40 and then use the Teflon lubricant. Not only does it keep the chain lubed without a bunch of unsightly fly-off, it also keeps it clean and looking good.
I've used both the spray-on and the squeeze bottle with the same results. The spray-on is quicker and easier to use, but the squeeze bottle is small and convenient to carry in the tank panniers on a trip.