Why would anyone get a twin keel if they could have a fin?

[Laser310]

It is obviously possible to design a performance boat with bilge keels. I saw this impressive yacht in Germany though I believe it is a French design. It is about 40' and, most impressive of all, has a steerable saildrive, which you just see.
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it doesn't look stiff enough to have much of performance rig though

i'm not saying it's not a good boat - i'm sure it's great for whatever the owner plans to do with it.