hey all, new to the board. i found a dewalt for around 480$ and i like it.

i've worked with scrolls saws befor but forgot some of my basics, so heres my questions.
on the description it talked about amps, what are they and what do they do?
strokes per minute, 400-1750 is this good?
stroke length is 3/4, is this good?
depth of cut is 2in, is this good?
thanks for yer help, jess