Trick-Tools Multi-Tool Grinder Attachment

[wellis77]

I'm going to be ordering one of these from trick-tools shortly and I need a new bench grinder to go with it. They sell it with a 1/2 HP and 1 HP JET bench grinder. The reviews on the 1 HP are mixed and I'm curious if anybody here has it, and if so what you are using for a grinder? Is the 1 HP necessary or is the 1/2 HP sufficient? Both units spin the same RPM. Thanks for your thoughts.