Google Tag Manage – to use or not to use

I don’t see any reason to change if all is working fine as it is, and you don’t need to add anything new supported by tag manger. I use my own plugin to integrate analytics and few other things, and I don’t plan to waste time doing exactly the same thing using different tools, and I am yet to see any proof that tag manager is better solution. It is more convenient, and you can decide to use it when building new site.