Setup is quick, tech support is excellent, and you can have as much power and flexibility as you need.
I would say that RoseHosting has provided a quality and reliable service at a reasonable price. My experience is that of a small business (brittfranken.com: photography). I have not tested RoseHosting VPS with regards to scalability (yet). With that said, for small businesses, requiring a certain technology freedom, RoseHosting VPS is a great solution.