I am just taking a stab at it here, but I would say the BEST is a detonation counter. Next would be EGT.

I dont know what you guys have over there, but I am about to purchase an EGT sensor system from Digatron. http://www.digatronusa.com/ Their DT-54K Max setup has 2 EGT sensors and a MPH sensor, which is ideal for my (now street legal) NSR. It also has laptimers, cylinder heat temp, and RPM readings, and datalogs over an hour of information. And I have found these for just over $400 USD brand new.

Compare that to a $1200 dual Det counter system, which is the going list price.
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Paul Herr
'88 FZR4/GSXR/YZF Frankenbike
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