Question about wideband air/fuel meter

[Blackone51]

Was wondering if its necessary to monitor both sides of the engine?
http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&rd=1&item=350143659460&ssPageName=STRK:MEWA:IT&ih=022

Or is the autometer cobalt gauge good enough?

 

[lvmustanggt]

I just bought AEM wideband from ebay for 204 shipped.

 

[squeak93]

Monitor the drivers side as its the leaner of the two. U can waste ur money on a dual system if u want, but no need to.