Built a DIY one w/ a microdose pump triggered at selectable intervals by ticks from the speedometer sensor.. kind a ridiculous level of effort to make but it works well. Had it on the Bandit for 6yrs or so, now on the R6. Keeps the chain very clean (meaning, if I clean it not much dirt comes off even after months of riding) OTOH the left swingarm does tend to get dirty. On the Bandit with the oiler running I probably put something close to 40k on the chain, was still going strong when I wrecked it- that constant washing off of dirt really helps. I set the interval such that I get about 1 drip off the chain when the bike is on a sidestand after a ~30min ride. I use the cheapest 5w or 10w motor oil I can grab, the reservoir holds maybe 10 to 12 oz and lasts around a month of regular commute riding, or a couple weeks on a long trip.