I put a B&M in my '97 GTS. Easy job (I am not a mechanic!). Depending on what year car you have, the hardest part is drilling out the rivets to remove the stock shifter...you need several drill bits. Gen I cars have softer aluminum rivets, Gen II have hard brass rivets. I paid the above price for mine after checking a bit. A definite improvement with new shifter...make sure to use the new upper shifter lever that comes with the kit (there's an option to use the stock upper shift lever with the rubber isolation...don't do it). There's minimal if any additional vibration with the billet lever without the rubber isolator and the shifts are more accurate IMO. You also have to drill a couple of holes in the transmission tunnel to get to a couple of bolts but it's not hard.
If all this sounds like to much for you, you might consider just changing to a shorter MGW knob and get a shorter throw. Some have done both but most believe the combination of the MGW shifter knob and B&M short throw shifter makes it so short it's more difficult (less leverage...especially for reverse) so I put the stock shifter knob on and like it that way.
You should check out the "How To" section over at .org for more details on installation.