Well it looks like it's going to be 20x22, which will easily fit in an Eddystone 111x60x27, that's the size enclosure I plan on using anyway. I'm a perfboard masochist myself, but I'll only be doing the one size layout (sorry Aston), it could be smaller but I want to make it an accessible and easy build for less experienced DIY'ers. If this project becomes popular I'm sure we could persuade John Lyons to do a run of PCBs.