Google Add Groups. How many kwywords?

Can somebody tell me how many keywords should I have for each of my add groups?

I've been doing some research and some people say to use as many as possible but others say to use from 5 to 10 closely related keywords about a specific product or service.

I'm confused, can somebody help?

Why not set up several different ad groups each targetting a set of very focussed keywords. The advantages are you can vary the maximum bid price for each group seperately, often the price needed to get higher up the page varies a great deal and this allows you to keep costs down.

It also allows you to see at a glance which ad groups are working and which are not from the main summary screen.

My website is very focused, and I still have two groups. One group has all the standard keywords and the seconded one has only the cheap ones (which I’ve called Low Cost Group). This gives me the flexibility of controlling costs by activating one or the other depending how my normal (SERPs) hits are doing.

raz