Stewart vs. Flowkooler

Now that warm weather is really here I figure it could be time to replace my unknown year water pump with a higher flow unit. Car is 67 El Camino, 327/327 and basically stock with Edelbrock carb and intake, original 2-row radiator, factory A/C car but A/C pieces not being used.

Car normally runs 190-200 around town (with 180 stat) and doesn't see too much highway use for any length of time. The 190-200 doesn't bother me as that's where it should be on hot days but I'm concerned about any 'reserve' area, if you will, for when I'm in traffic. It doesn't take very long to begin creeping up to 220-230 range.

I'm looking at either a Stewart or FlowKooler water pumps that are advertised to give 30% more flow at low speed stop-and-go type traffic. I don't mind the 190-200 typical temp but would either give more of a cushion before creeping up to the 220-230 range?

Both about the same price from Summit, <$100, so that's not an issue. Any good/bad for either make?

TIA!