> Something you don't cover is my pet peeve with Duplo/System
> compatibility: 2x3 system bricks.
SNIP
> A few notes about Baby (Primo): it is compatible with Duplo via
> http://peeron.com/inv/parts/31007
> and Primo bricks do fit neatly onto Duplo studs (but with a
> half-Duplo-stud offset). Primo has no clutch power.
>
> There is another large brick system, Soft,
> http://guide.lugnet.com/set/?qc=dacta/legosoft
> which (IIRC) is directly compatible with Primo.
The 4777 Knights Castlecomes with
three enourmous Duplo plates which also
attach perfectly, and using them is an easy way to combine the Quatro/Duplo
systems. You can build a large base of Quatro, stick the 8x16 Duplo plate on
top, and then continue.