Its a personal choice to hire a consultant, yes it takes lot of time to understand the filing process, not many people do it on their own.
But as smip said any loss will be yours.It is also not the consultant who is important but the person from the consultant who is interacting with you and filling up the form. The consultant will always have business angle to the whole process as he has to make money from you.
In your case since you are not comfortable with filing on your own i would suggest you meet all the mentioned consultants and go with your gut feel (although everyone seems good before getting hired). Make sure not to give whole payment in advance at any cost, have the payments split phase wise, that is some at the time of filing some at the time of AOR aome at the time of Medical and the final at the time of stamping. Even if they offer to give concessions for complete payment at the start.
Also make sure to not to leave everything on the consultant. Interact with them at every minor stage and ask lots and lots of questions. Put your foot down if something seems fishy. And of course you can always take advice from seniors here who have and are going through the whole process themselves.
Sunny