There have been some problems reported with the Witness line. Do a search here or on some of the 10mm forums. I have not had any problems and think they are worth a shot. Between the two mentioned the Match is a much nicer shooter.
One of the "problems" with the Witness line is they were (and I assume still are), sprung for standard 10MM loadings. This means the hotter loads can beat them up some. If you are going to be shooting Double tap or Buffalo Bore or similar I would recomend upgrading the springs. Make sure they balance out.
Just for the record if you find yourself flush with cash look at the STI line. They also make some nice double stack 10mm's.
It is in my nature to like Sigs