LUMSING Macbook Air replacement battery

I am thinking of purchasing a replacement battery for my 2011 13" Macbook Air and was wondering if any of you had any thoughts on this replacement. It appears to be about the least expensive and ships from Quebec City. I had never heard of this replacement before seeing it advertised on ebay.ca.

Any thoughts/experience greatly appreciated.

Silver Back

via ehMac.ca http://ift.tt/2euAno3