mine came with a 16gb, the larger the card the longer it can record before the card becomes full, and it is
necessary to over-right existing recordings.

Obviously if you have 2 cameras then the card will filly up around twice as quick - assuming both cameras record at the same settings

http://www.blackvuehd.co.uk/Blackvue_FAQ.php 

Ive noticed a couple of sites selling the Blackvue. If its not against forum rules - where did you guys get yours from?

got mine on the bay of fleas, as had some cash in Paypal account ( from selling old cr@p I found in my garage)

couple of edits to original write up.... 

Mine was supplied & fitted at Sounds Alarming in Welling, North Kent / SE London. I will be getting them to do me another. (Past) Freelander 2 HSE 2010 MY In Rimini Red.
(Past) RR Evoque Dynamic Lux Si4 In Firenze Red.
(Past) RR Evouque Pure Tech in Barollo Black with bespoke Firenze Red colour coding.
(Present) Freelander Metropolis 2015 MY In Santorini Black with Ivory Premium Leather.

might be useful,

Obviously the 600HD takes 64GB cards, so just double the time given for 32GB cards
and, If you have two camera systems recording onto one card then reduce the recording time accordingly

 

Just got myself a brand new DR500 to use as a rear camera for £91.11 on the bay of fleas.

bargain. 

I was looking on ebay & see there is a DRB750 now. Looks good but one seller (probably a more honest one) says you can't use is if the car has DAB radio. Anyone know why that might be? (Past) Freelander 2 HSE 2010 MY In Rimini Red.
(Past) RR Evoque Dynamic Lux Si4 In Firenze Red.
(Past) RR Evouque Pure Tech in Barollo Black with bespoke Firenze Red colour coding.
(Present) Freelander Metropolis 2015 MY In Santorini Black with Ivory Premium Leather.

I understand the co ax cable between cameras can cause issues with DAB reception - at least on older models.
Perhaps this newer model has better shielding.