If it was easier to use than Miami ie. offered some kind of functionality improvements I'd buy one... as it's always a struggle to find my current version of Miami or some other stack and get it working. Plus Holger has not developed Miami for ages... and seems to have stopped taking registrations as well.
So as long as the rego is reasonable... there seems no reason not to jump on it early rather than later.
Alternatively if the rego is a bit steep then I'd first evaluate it and then buy it.
:-)