Pros,
Cheap compared to alternatives.
Customizable
Durable
Protects the rim
Personally I love the look as well
Cons,
They do cone in (if you want to call that a con some folks like the look it produces)
Some say illegal (I've been pulled over with them on in a strict state and nothing was said)I have yet to see it in black and white.
Rim is permanently altered.(if you want to call that a con)
They don't lock the inside bead. Cheap ways around this as well.
Generally I don't do bolts with them for the simple fact that the weight of the bolts would require them to be sent in a different package which negates any savings I could give you short of picking them up at a local hardware store. I also have seen instances where a shorter bolt could have been used. I'd start with 1.75", 1.5" will often get it done.
I was going to stay out of this thread as I am biased but hey, there it is. Fair as I can be.