I have plans to buy a wide band setup or build one
Australian DIY Wide Band Information
but for now I have 2 auto meter narrow band meters ( when my MR2 failed emissions I just went down to auto zone and bought one then another later for a second car)
I like the auto meter it works great you just have to guesstimate a little since the thing is fluctuating back and forth so you just use the center of the swing
HTH
Davegt27