Hull Draft vs Stability

[jmac]

I am looking for a boat that will Sleep 4-6 around 36ft. I would like to see max 15knots with around a 12knot cruise. My other requirement is safety. I live on Lake Erie and within a relatively short time the lake can go from calm to 10ft waves.
I am currently looking at plans for a Waverunner 34 (http://www.bruceroberts.com/public/H...escription.htm) which has a draft of 3ft 11 and a beam of 12ft.
I am also looking at the Stadtline 38 (http://www.stadtdesign.com/products/vds431.htm) which has a draft of 2'11” and a beam of 11ft 8”

Am I wrong to assume that the deeper the draft the more stable the boat is. Of these two boats which one do you think would be more seaworthy and fuel efficient at the 12 knot cruise.

[Raggi_Thor]

There is no simple relation between draft and safety.
Both boats look very safe indeed.
The Stadtline 38 is a bigger boat, 7.5 tons vs 4.5 tonns for the Waverunner 34. The Stadtline is CE cathegory A which means you can cross oceans with it.

[jmac]

Thanks Ragnar

You mention weight. Would the same boat built in Steel Vs Aluminium have the same caractaristics?

[Raggi_Thor]

I don't know how much lighter it will be in aluminium vs steel.
The boat should be designed for one of those materials I think.
If displacement changes significantly, the underbody also should change. A steel boat could for example be a little wider than a simmilar alu boat, to make up for the increased weight.

If you like theese two boats you have to talk to the designers, they are both well known companies.