a group of us were talking about these the other day. My one buddy (roadconetuning) has one and said he didn't recommend it, but didn't state why.
I've got the NGK powerdex and love it. It was $240 shipped brand new, and isn't a "gauge" style. Its completely digital, and shows the AFR like what my tuner has (small box w/ the AFR is numerical format). It also has an analog output for your datalogger or autometer, etc AFR gauge.
one of the reasons why i'm considering the aem is because its a gauge style...i'm just curious how it looks at night. If it looks like crap i'll go with the autometer NV wideband and boost gauge but the aem boost gauge is also digital numerical display so i'm not sure what combo i wanna order.
ask your buddy if he can post up a night shot of the aem wideband...thanks