I'll start...

I like a couple of types of wood. A nice buckeye burl (which might be what you have on that model 4) or redwood burl is hard to beat. However, the right piece of Curly Koa can make a fine looking knife as well.

I tend to prefer NS hardware with the redwood or buckeye but the browns and golds of the Koa go very well with either brass or silver.

For me it's pretty much a matter of taste/opinion so I'm interested to see what other folks have to say...