I'm interested in understanding which is best way of retrieving nodes that are located in a branch different from the one where my current node is.

At the moment I'm doing:

var entities = Umbraco.TypedContentAtRoot()
        .First()
        .DescendantsOrSelf("Taxonomy")
        .Where(x => x.Name == "Bodies");

But I was wondering if, performance wise, it's better to first select the specific root, and then search only inside it.

var entities = Umbraco.TypedContentAtRoot()
        .Single(x => x.DocumentTypeAlias == "Settings")
        .Descendants()
        .Where(x => x.DocumentTypeAlias == "Taxonomy" && x.Name == "Bodies");

In theory I could also store in my app.config the actual node of which I need to list the children, but I'd prefer to avoid doing that.