macs
over time even a mac can slow down to an almost complete halt. we've all been there.
sometimes it's a simple matter, other times it requires a little more investment, but there's no reason why a mac shouldn't stay 'state of the art' for many many years.
take me for example. i'm rocking a powerbook g4 and it still goes like a bandit running from the feds.
pcs
these days pcs have caught up with macs, mostly thanks to windows seven (which the mactrician is happy to recommend).
for those of you on older systems, before you decide to spend money on a new machine, call the mactrician, because there's a lot you can still do to make your pc fly straight.
