That was pretty deece.
I'm not sure what, if anything, determined when I developed the knowledge to purchase higher upgrades, but apart from that it was a fun time.
Agreeing with the other review, it can be somewhat of a grind at times: capture a few subjects, infect, pass time to let infamy die down/more buyers to show up, repeat. However, once I was done upgrading to the maximum...my final serum was equal in stats to my beginning serum...oh well?
While a tiny bit of a slog at times, this is a fun little experience that does what it sets out to do - as such I recommend it!