From what I remember...
No need to rehydrate
Use two packs when OG is over 1.060
Can pitch directly into wort and not lose half the cells
Once a pack is opened must be used within a few days
And dry yeast can be reused up to 5 times before tossing
I just purchased the spike CF-15, and yes it was more expensive then the others mentioned here...but as stated it’s a one time buy and can do everything you need in a unitank and do it well
Not sure if this was addressed, if you buy Fermentis in the bulk package, you’d need to use it all within 7 days according to the rep who spoke at nano-con