i did a lot of research on them before i discovered the M&P
the first ones (SW9V) had problems fte,ftf and trigger.
they were so close to a glock 19 that glock took them to
court and smith had to change ths design, parts would
interchange with the 19 they were so close.
now smith has to give glock a piece of everyone they sell.
the new ones (SW9VE) have had no problems, they do
have a very heavy trigger, that is the only thing i have
heard bad about them. same thing goes for the .40 cal.
you can tell the first ones from the second ones at a
glance. the first ones have a black slide the second have
a polished slide. never owned one but have shot several (first and second)
i think you would be
safe with one. i bought the M&P because it looked better
and seemed to be built a little stronger it has steel framing
inside the plastic frame. seemed more sturdy than the sigma.
sorry for the long post, but i hope it helps