In this comparative study, we examine the influence of two different FEM discretization techniques (conforming Q2/P1, nonconforming Q1/Q0 Stokes element) and solution procedures (nonlinear Newton variants and multigrid vs. Krylov-space solvers for the linear subproblems) onto the approximation properties and particularly the total efficiency of corresponding CFD simulation tools. We discuss algorithmic details and give numerical results for laminar incompressible flow examples including non-Newtonian behaviour of power law type