Hi 
Just a mention that I had a genuine Mazda 2 6CD changer fitted by the
dealer I bought my car from - cost £50+vat for fitting.
To buy and have fitted by dealer was £300 but I bought mine off Ebay
boxed & brand new (never used) - cost me all of £41! Including p&p!
Bargain - less than £100 all in. (£99.75 - 9 months ago).
Thought somebody would like to know that you do not have to buy from dealer.
Ttfn - Michael 
P.S. The slight drawback is that once fitted I had no guarantee if the unit
happens to fail in the future because I bought it privately. Works great!
P.P.S. Also kept the original single CD player/radio in case it's ever needed?