Comparing something to mashed potato definitely won't convince me to go with something else... yum. :P But I spent a good chunk of the day looking for retailers in my area, and I finally found one. It's conveniently placed, but I'm not actually 100% sure it has what I want. I'll be phoning them when I can, to see if they do. So I'll likely be buying something other than plaster of paris.

So I can see that the advantages of HA molds are many... the reason I'm buying them is mainly for a great finished product (and a fun time making it!). I could very easily imagine myself building much more than playing.