FMTC aims to provide all the functionality you will need for caching, in a way that requires little knowledge of the internals of 'flutter_map' and other caching fundamentals, and little effort from you (for most setups).
However, there are two main concerns that apply to most people:
Can you abide by the GPL v3 license, or do you need an alternative proprietary license?
See (Proprietary) Licensing for more information about this
Do you require all the functionality and control that FMTC offers?
Answering the second question is the more difficult than answering the first one, but it will tell you whether it's worth your while getting an alternative proprietary license if you need it.
You'll want to consider using FMTC over a custom DIY solution if you need any of the features below. These take a long time to reproduce and get right, but we've already done the hard work for you!
You need to provide bulk downloading or import/export functionality to your users
You or your users need a lot of fine-grain control over the cached tiles
However, if you match all of the following, you may find that a DIY/custom solution will work better for you.
You are developing a proprietary application, and we can't reach an agreement for an alternative license
I aim to agree a price or deal that works for the both of us, so please do get in touch even if you're unsure if you can afford a license
You need only very basic caching
You need only browse caching
If you're still not sure, please get in touch: Get Help. I'm always happy to offer guidance :)