... but, yeah ... I like RR's for trolling. I've caught a lot of nice Crappie from several different lakes, trolling a 1/16oz RR (marabou). Usually troll them on shallow flats, or along the outside tops of fallen trees (if I can find a bank with a number of them along it).
For longline trolling, I usually employ several different brands & styles & colors of jigs, just to give all the fish around ... something different to pick. Size/weight is a mixed bag, too, so I can cover more depths AND size preferences, at the same time. They can range from 1/32oz to 1/8oz, and be all hair/feather/artificial material ... jighead/plastic body ... or combo of both.
Can't really give you a MPH "speed" (no speed indication system onboard) ... but, I'm usually a good cast's distance behind the rod tip, and the bait will drag bottom if I get into water shallower than 6ft. I usually only get to do this type of trolling during the early part of the year. If I get to go during the Summer months, I'm usually casting during the early hours of the day. And during Fall, it's casting to submerged timber that's in deep water ... or shooting docks (where available). May even be dipping a minnow/float setup into some standing Cedars ... again, depending on the lake.
...cp