I say none cause the 8020b are very small speakers which extend to quite low frequency for their size and therefore will have to use ported designs, which in turn will lead to extended woofer excursions(and less controlled excursions + high Qts) which also means production of low harmonics which in turn mean that those harmonics distort and affect the mid frequencies ...etc etc etc
Quality studio monitors should only sound pleasing when the mix is pleasing, unlike Focals which make everything sound bearable. (A 2 year Focal Twin user + treated room user speaking, I also had Focals CMS40 for the recording studio)
Cms 40 don't strike a big contrast between bad and great mixes, they are also forgiving with regards to the high mids and high frequencies + the colored low end and mids. I also should add that the stereo image representation + depth representation = very mediocre.
Might be good to amplify your stereo T.V system or find a good place in your kitchen, but as a PRECISION and REVEALING STUDIO TOOL ... no way.
Besides, Focal says that they use 4" speakers in the CMS40 when actually they use 3.5" speakers. Which tells you a lot about the integrity of the company.
You would be way better off with a Neumann KH 120, they are way better precision tools than Focals "Twins". Save some cash and save your health(yups frustration causes health problems).
Sorry I never worked with Genelecs and I cannot advise you on those.