Does not seem to be a Sinclair. Red sticker does not have proper printing on it. I believe that the Sinclair has a special pump and valve. As to whether it is better or worse than a Sinclair who knows. It is common to see knockoffs $100 or less. I have no idea why someone would choose such a complicated thing with such a small market to copy.
2000 Montague CX, I do not recommend it, but still ride it.
Strida 3, I recommend it for rides < 10mi wo steep hills.
2006 Rowbike 720 Sport, I recommend it as an exercise bike.
1996 Birdy, Recommend.
Wieleder CARiBIKE (folding), decent frame.