Many marketing experts will tell you that on average, converting between 1-2 percent of your visitors to buyers is a an acceptable conversion ratio. But I disagree with that "one size fits all" theory. I believe a good conversion ratio is any ratio that provides you with a satisfactory profit margin for your business. That can be as little as 1-2 percent or less, or it can be as high 5-10 percent or more. However, only you can determine what a satisfactory profit margin is for your business. No one can do that for you. David Jackson Fundamental-Marketing-Blog.com
I would agree with you on that. It will vary based on the website and what kind of marketing methods were used. I tend to think that a ROI of +15% is about my limit though. But like you said, only those who own the site can decide what is right for them.