It depends on what your end goals are. If you are going at it alone, this, or any other service should suffice. If you are also thinking of implementing a custom process and your company will have "secret sauce", you are probably better off developing your own solution.

A few points to consider:
* You want to make sure the product you use is reliable and safe. You will be storing PII for your candidates, the app has to do a good job protecting PII
* From what I can tell, you still need to deploy this app yourself. If you don't have technical expertise, I wouldn't recommend it. You would be responsible for its reliability scalability, and security which is not trivial. An alternative is to use a SaaS product, which comes with all of the above managed by the provider

Usually, already built solutions offer a process that you have to follow in order to use them. In other words, you don't adapt them to your processes, you adapt your processes to the tool. If you are a new company and are low on cash, use the solution. And when you start making money you invest in your custom platform, unless your new company is based on your software product.

It depends. If it can support your operations and you feel it adds value to your organization you should probably go with it. Remember that programmers and designers are very expensive, and will (rightfully) charge you many thousands for custom development.