I have also just recently added an Apexi RSM (Rev/Speed Meter)... Its basically a device thats wired into the ECU and gets the RPM and speed from the computer... It has does quite a few other things as well...

0-100k
0-200k
0-300k
0-100m
0-200m
0-400m times...
As well as a few other things...

For 0-100k times the best i've done is: 5.34 seconds...
and for quarter mile (0-400m) i've done 13.34 seconds...

Well i got the Skyline dyno'd today!!! 245.3BHP!!! or 184Kw at the rear wheels!!! Check out the dyno sheet: