It works pretty well with Roadstriker level mecha (power suit to landmate size).
Having just a couple of super robots distracts from street level cyberpunk shit, so does military style stuff associated with 'real robot'.
You can certainly just add some CP2020 stuff to any Mekton campaign, but unless you are focusing on the "high-tech low-life", it misses the cyberpunk bit.
Megazone 23, Dominion Tank Police, Bubblegum Crisis (and others) provide a look at what a cyberpunk style game with some smaller mecha can be like.>>63414812
I'm not super keen on any of the established settings for Mekton (unless you count Jovian Chronicles).
A big thing for me is the mecha creation, which is also kind of like setting creation. A game set in Algol with pre-set Mekton designs (even if they are somewhat modular as in HBS Battletech) is not super interesting to me.
Now, a game that was a little more like Master of Orion crossed with Rule The Waves, but with giant robots - that is fucking awesome.
A game with a small group of player characters and a super robot or three versus the weird giant badguys, also including mecha customization, that would be pretty cool too.