Let's start with the most obvious question to ask of any

1. What is the Track Record is it Real or a Back Test Simulated?

Most Forex Broker have never made any money and rely on past result simulations on paper and of course this is easy, they are hindsight traders! Others present what they claim are real track records but these track records are not independently verified, so just forget about them and keep looking around.

So only go with truly tested independent audited results. If you do check this it will eliminate over 95% of them.

2. What is the history of the designer or Broker?

This will give you a good insight to the reliability.
If you are going with a program be aware or beware that most are not designed by traders, and they don't at times have the real understanding of the markets.

3. Do they disclose all the rules?

If it is a black box system, don't bother, if they are so good would someone really sell it? If you have a great money making guaranteed machine would you sell it online or would you just keep raising the stakes and make all the money yourself. Guess how most black box makers make their money, you guessed it selling it. Not from the Market.
IF you are looking for a great Broker feel free to visit the they have recently researched all the brokers and have found what they believe to be the best. If you are looking for extra educational lessons they have a lot for you to learn from.

4. What support is on offer?

Before getting involved ask what support you are given. It is real time, is it quick and honest.