I own a Sinclair-Wilson with micrometer, two Forsters, and a Giraud (sp?) power trimmer, I have owned and used Lees, Forster powered, Lyman and a few others.
For average, everyday use, buy a Forster. They are simple; they have relatively inexpensive adaptors; and they are as precise, or more so, than any other. They work for pistol and rifle and can be adapted to a very wide range of cartridges, long and short.
If you want to do large lots of bottle-necked rifle cases, the Giraud power case trimmer just cannot be beat.
L.E. Wilson and the Sinclair adapted version of the unit, are also very precise and work exceedingly well. There are some specially adapted tools for this unit.
All the rest are, IMHO, second best.