It all depends on how much mileage you do, and what weather you ride in.
Red Scottoil is useless in the winter as it doesn't flow due to low temp, and blue Scottoil washes off in the rain.
Regular engine oil is the best if your a 365 biker as it flows in all temps, and doesn't wash off as easily. I just use cheap supermarket oil and fil it up every time it gets low.
As for making a mess, well you have to degrease your back wheel anyway, so no change there then.
Other tan that if your fair weather or recreational rider, blue Scottoil is fine and will double the life of your chain!