Start a Service or Product based business?

I know I haven't posted in awhile, but I'm hoping that those out in cyberspace can help me out with a question that has been bouncing around in my mind relating to starting a business.

The business I have always had in mind is a "computer service" business because it is what I currently do for a living and is really the only area I feel I have expertise in. My worry is that as a service based business, I may be dooming myself because the business model its not easily scalable (at least not in my mind).

Would you continue down a "service based" business route or find a product, get some new expertise, and sell the product?

Any comments are welcome.

Thanks,
Jason