Firm feel manual box rebuild?

I have a standard 24:1 manual steering box from my 74 duster needing a rebuild.

I talked to firm feel about rebuilding it and quoted me $330. They said for an aditional $225 they can upgrade it to either a 20:1 or 16:1.

Should I go for the upgrade and if so which ratio. I am doing some mid grade suspension upgrades for better handling and Im sure I would like the 16:1 the best in the corners but would that kill around town drivability with the weight of a small block up front?