Both those karts have been imported into the States before. Mach 1 had an importer out west for a while and I believe someone in PA for a while as well. Formula K was in the states last year with Champion Racing.
The best example of a top level driver winning on whatever brand was Scott and Alex Speed. I didn’t matter the kart, they were ALWAYS up front. So with the right driver and support any kart can win.
Support is the key in karting in my opinion.
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