Is full-frame necessary for wedding photography?

Hi all,

I am a pro-am photographer and of late I am getting more and more bookings for weddings so have been thinking of the best (and most cost-effective) route to full-frame. My 2nd body is a 20D which is now very dated and totally ineffective especially for low light / high ISO work.

Should I wait for the 6D (seen the spec and price and not impressed for the money being asked), buy a 5D2 (they are now around the £1200 mark) or do I stick with crop and just get a 7D to partner my existing gear (see below).

What do you suggest as the best upgrade bath to take my wedding photography to the next level

My kit at the moment:
Canon 50D
Canon 20D
Canon 70-200/f4 IS L
Canon 85 f/1.8
Sigma 18-50 f/2.8
Sigma 10-20 f/4-5.6
Canon 580EXII and 430EX
Phottix Odin wireless triggers

Thanx in advance
Alexis

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