We've just launched our site, and we're stoked! Thanks to all the support folks who answered my many questions.
The site is a reasonably complex combination of Cart66 and Gravity forms, with the largest Gravity Form coming in at 259 entries (booklets: http://australiandiscountprinting.com.au/cheap-printing/booklets). My favourite integration with Gravity Forms though is for Business Cards (http://australiandiscountprinting.com.au/cheap-printing/business-cards) and Calendars (http://australiandiscountprinting.com.au/cheap-printing/calendars) where we've hidden the information required from someone needing a custom job behind a single drop down: "Graphic Design Required?"
Anyhoo, check it out, let me know what you think!