[samsheen]

I believe that the question you should be asking yourself is this - Can BaaS (or any other service) help me get to the market right now at the lowest cost possible.

For any such commodity as a service, the initial costs to you will be lower than if you had to build the service yourself. However, over time the costs will go up. The benefit to you will always be ease of development and having the time to focus on building the core features that will make your startup feasible. Most startups fail before they reach a point where they need to worry about rising costs and that's a good problem to have. (when you have it you can mostly pay someone to fix them for you)

My recommendations (having never used any of the above mentioned BaaS providers, do take these with a pinch of salt)

1. Look at how easy it is to get your data back if you need to host the services yourself or change providers. Does the provider have any processes for the same? Speak to the sales (and support) people about this before you decide on a provider. Look for the provider that is transparent about this.

2. Don't worry about what the cost will be when you reach a million users. Your time right now is spent wisely validating your idea. Cross that bridge when you come to it.

3. The only "complete no no" scenario I can think of would be if you were hosting sensitive information (credit card etc)

Hope this helps