If it was my ride, I would probably go with a bolt on setup. My reasoning would be, welding the chassis could jeopardize the structural integrity and if for any reason the welds ever crack, having to weld over the same area will just make it that much more weak and even more prone to crack again. If you don't live in an area where you will be slamming up against some rocks on any kind of a basis why not go with the bolt ons? I would sure rather have a bolt shear and it still protect my vehicle then break some welds on the chassis and possibly damage the chassis in the process. With the bolt on application you also have the option of easily taking the sliders off if you feel the desire to do so. As far as bolts go, if you are worried about shearing them you can get a handful of aircraft quality bolts that are well over twice the strength of G8 bolts. You could also go with titanium bolts that have the tendency to flex rather then snap in abusive situations.
I'll be straight forward and tell you that I DO NOT have much 4x4 experience at all. It just seems to me like a weld on application would be for someone who is doing some serious 4x4 action in very extreme situations.