I hope nobody is expecting the CBR250 to be quicker than existing 250s, because it isnt.
as to Hyosung, I worked at one of the 1st dealers in the country to carry the marque, and while the designs were solid, the materials were just crap. Especially the rubber, hoses rotted at record pace.
About 3 out of every 10 650s would develop a nasty motor knock, and Hyosung would throw a fresh motor at it. I never had a chance to tear one down and see what was going wrong.
That was 5 years ago, so hopefully their build quality has improved.