Adrian that is an interesting one.
I like that and they have not taken to big a chunk for putting it together.
Here's the rub though.
Are you wanting to do all the work, on brewday, or will you want the machine to do some? Because there is no pump and no digital controller. So this is no more than brew bag in a plastic bucket.
Futureproof. Meh. I suppose it is easier to fix, but there is not a lot to go wrong. The residual value is higher, but a bag and a bucket are cheaper in the first place.
So the question becomes what sort of brewer are you and where do you think you brewing practices will lead you?
If you are a bit handy, this will be a good base for building as you go.
Just get some hop bags or make some. An experiment by Peter Wolfe of Oregon State University found there was no difference in using a bag or throwing the hops in the kettle loose in the IBUs when measured on a spectrophotometer.
