As for me, the most comfortable tool for backtesting is Forex Tester. For sure, it is not free, but it has more useful feftures than the other. Now it is only for forex, but they have already announced stocks testing in the upcoming update.
It is up to you, but I would rather recommend to find a better player and follow him/her. You can learn from consultant in a shorter period and again website or any application will give you just general recommendation, which are not necessary will help in particular situation.