  We test equivalences between different realisations of Wilson's
renormalisation group by computing the leading, subleading, and anti-symmetric
corrections-to-scaling exponents, and the full fixed point potential for the
Ising universality class to leading order in a derivative expansion. We discuss
our methods with a special emphasis on accuracy and reliability. We establish
numerical equivalence of Wilson-Polchinski flows and optimised renormalisation
group flows with an unprecedented accuracy in the scaling exponents. Our
results are contrasted with high-accuracy findings from Dyson's hierarchical
model, where a tiny but systematic difference in all scaling exponents is
established. Further applications for our numerical methods are briefly
indicated.
