Fluent Solver
 

For real gases flow simulation is pressure based or density based solver more accurate ?

You can do either pressure based or density based solver for Real Gases, since they do on affect how the gas properties are calculated.

The choice of whether to use pressure or density based solver to begin with is more important.

In general, stick with pressure based for incompressible and density based for highly compressible flows (unless you know your flow needs density based for whatever reason, go ahead and use it).