In absolute terms, if these tools are useful to you then you most likely make enough that $25 is an inconsequential amount of money.

But relatively speaking, with 1) no way to preview functionality; 2) no way to preview code for quality; 3) the inability to get a full refund if they turn out to be garbage; 4) having to download executable instead of just running them in a browser (even though they're apparently written as web apps); and, 5) not having any idea who this person is, it's a big ask.

It’s a bunch of stuff you can get for free and web based by googling. It’s probably more convenient for me to use the free ones because I can the have a list of bookmarks to the things I use. Also there are free dev tools out there I might need that are not in this kit, so I’d need that anyway.