FSPGX is a Russell 1000 Growth index fund (which is the gold standard index of this type). Can't go wrong with this one!Added some FSPGX and VOO to my Roth recently. Fidelity has so many different funds it was tuff to choose one.
My 2 biggest growth funds are:
FDGRX (Fidelity Growth Company) - best in the business, but closed to new investors
FBGRX (Fidelity Blue Chip Growth) - also outstanding, I use it in accounts where I don't have access to Growth Company
Maybe you should add a little extra juice to your Roth account? :)