I run a little behind on reading Fine Wood Working, so I'm just getting to March now. There's a review of honing guides in that issue. Not surprisingly the reviewer liked the Lie-Nielsen and the Veritas mk II the best. He did comment that the mk II is very sensitive to the pressure applied by the two clamping knobs, and that uneven pressure will skew the edge.
Thing is I know this and am careful, but still get a skewed edge. So I don't know how many decimels of precission are expected from the operator.
The review also gives the older Veritas Sharpening System (mk I ?) A very good rating. This is a single screw top clamp device sold with a jig to determine angle. Looking at it this might be a better compromise. I have too much invested in the mk II, and don't spend that much time with planes and bench chisels (my woodworking has spun off in another direction), but if I were going back in time I'd look at the mk I more closely.