I think they are 5x7" on all models, not sure about EU sizes though.
I've always had very good luck with Pioneer speakers. I had them in my Mustang and never had a problem. I've got some non-pioneer speakers in the Focus as they were a gift and I'm not "unhappy" with them, but I'm not completely satisfied with them.
Be sure to install them with baffles to prevent panel vibration and to get the clearest sound from whatever speakers you buy.
2011 SES 5spd #006 >> SR #213
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