Ench+BS here
For some reason I can never remember the alchemy trinket. Not sure why, although I'm not that crazy about it. I like the mastery on it but the rest is a bit meh; the stamina is unnecessary and the socket is useless. The +40% on healing potions is kinda nice I guess but I almost never use healing potions. All and all, it seems the trinket is trying to do the job that several other trinkets that do it better; the TB trinket for mastery and Vial of Stolen Memories for stamina, and both have a better use function.
It's probably good for entry level, before you have access to other trinkets but I wouldn't use it after better ones become available.