Ive used just about every wideband you can probably think of.

My personal favorite for most people is probably the PLX for a couple reasons.... Not very expensive, Accurate, Stable, sensors are cheap and dont fail as often as some of the other bosch sensors ive seen...

not a huge fan of the aem, seen too many screw up.

 

We have used the zeitronix for about a year now and the bosch sensor is still rock solid. I believe Bosch rates the sensor for 100,000 miles. LEADED FUEL is what kills sensors 90% of the time. Do yourself a favor and use alky or meth injection instead.

 

in agreeance on the AEM wideband. pretty flakey. a wideband 02 controller that can run an NTK is also great, as the NTK is very lead resistant.

 

It depends on the type of racing that he will be doing. For road racing running 12 on 100 octane is too much. I prefer 11.5 or 11.0 on 100 octane. I do not know about drag racing, but 12.0 might be ok for a short period of time.

 

Depends on timing, egts, type of fuel. IMO on 91/93octane tune for an 11.5a/f and then SLOWLY increase timing. Watch EGT's and add timing up until either you detonate or better yet quit making hp on a dyno. 100+ octane you can get away with 12.1-12.5a/f .

 

AEM UEGO HANDS DOWN, for the quickest and most accurate i have found that to be the best but like other people have stated above me its all personal preferance but i can assure you is you go with the aem uego you cant go wrong, you wont be dissapointed, lataaa