What are the spec's of your tune?

I just ordered a Wideband Air/Fuel guage from Amazon. Its from AEM Electronics and has both Analog and digital displays. Part# 30-4100. Summit had it listed for $199. Amazon had it for $167. I had to pay CA sales tax but still saved $25.
With this guage/meter, I'll be able to register a baseline. From there I'll have a clear record of what effect each change makes.