Knockout Postcard Color + question (Patreon)

Finished him : )

Gonna see about getting this and Rodimus printed, but before I do, question:

For the Hound postcards I made the mistake of selecting A5 instead of A6 (postcard size), but the A5s looked really nice, showed the artwork well. However, I had to put the price at £4 on my shop instead of postcard price £3. I'm torn so I thought I'd ask you all: 

Which sizes do you all prefer?