You don't have to remove them to get the valve covers or the body panels off, they go on/off easily with three bolts, you can mount any 1" highway peg bracket, and they have a boss for additional lights.
The Ztechnik guards look the best and very inconspicuous. Not sure if I am reading the instruction right but the only issue is that they attach to the cylinder head on the right side and the oil line holder screw in the left side?
Yes, those are two of the six attachment points. You will find the screw for the oil line bracket is substantial. Two other attachment points are on the front of the cylinders and the main ones are two large bolts into the lower engine case.
Did have a pretty serious crash with these bars on my '10 RT. ZTechnik replaced the bent one charging only for shipping and the bars protected the bike's engine. Replaced a lot of plastic and rode the bike another 50K miles.
I have the Ztechnik crash bars mounted on my 2012 RT. They have performed well after two tip overs in 4 years . They look good as well. One down side is ,the side case will make contact with ground but the engine is protected.