Don't you think infinite supply will play role of pressure element on he price of coin ? There is lot of hype before the launch of this coin what is scheduled in two days now. I hope they will be much more careful with security and safety as first impression will be the last. We saw what happens with Beam with vulnerability. These are the two coins succeeded to get attention of everyone in very short time.
It is true that Grin will have an infinite supply but after an initial inflation of 400% it will tend, year after year, to be smaller and smaller, up to 0.
In fact you will have 86400 Grin every day, every month 2592000 Grin, every year about 31000000 Grin, but this means that after 10 years there are 310 million Grin in the market and the inflation will be 10%, after another 10 years it will be 5%, and so on.
Grincoin will not be a store of value with eg Bitcoin, and in fact its purpose wants to be another.