[sdiy] What do you use for pannel cutting / routing?

[Julian]

I need to cut some holes in some front panels.  They're about 3mm thick.  Im
wondering what the best way is.
 
I dont need a perfectly clean cut (for this project), as the edges will just
be covered anyway.
 
My thoughts so far - 
 
Mark out a template in cad with a load of cross hairs, and drill a huge
number of holes along the line, then generally manhandle the section out
with a pair of pliers, or - 
Angle grinder (probably a little vicious), or - 
Jigsaw with metal blade
 
or even - 
 
I keep seeing those dremel tools with cutting disks on the ends of them -
are those dremel multi tools actually any good? And are they up to a job of
this calibre?  

Obviously it would be nice to get skillfull at it, so I can do pannels with
exposed edges in the future too (I have a speak and spell thats midi'd and
keep meening to make into a module in my modular, for example...)
 
 
Any comments would be most welcome.
 
Cheers, Julian