How reliable are these adwords of google?

I bought google adwords package I'm bit confused with them as they are charging before starting the program. Anyone using this, pls help?

Please don't be confused. I think, Google Adwords is the best PPC Program among other PPC programs. I'm also working on Google Adwords and it is fantastic. And of course, it is reliable. I'm suggesting you that please use Google Analytics, to track website traffic and conversions. It is very easy and simple. You will see Analytics tab after Reports tab.
To ensure that accounts do not place unnecessary load on their advertising servers, you need to keep the overall number of keywords in your account to a manageable size. When you approach an unmanageable amount of active keywords, they will place a notice within your account and request that you refine your keyword list and remove unnecessary keywords.
You have take right decision. Go ahead with Adwords. You will know its benefits. Don't be confused.