I really like mine! I usually ride a 1988 Kawasaki Concours 1000cc sport touring bike and have over 34 years of continuous motorcycling experience.
I bought the Sierra purely to return to the fun of riding a light bike. It handles fantastic with the street tires, maintains 60-65 freeway speeds without straining too hard and is reasonably stable at speed. I was really suprised at the freeway capability from the 200cc engine, but mine also has an FMF TubineCore universal muffler. It's too loud for my taste but the power is there. The bike is really simple to work on and many Yamaha TW 200 parts interchange, especially engine parts.
I'm really happy with it but, would recommend it only to those willing to work on thier own motorcycle. Dealer support is rare, but some independent shops may do some basic work on them. The internet is a wonderful thing for parts and information on these bikes.