I agree with Brad.
If you can cut the heads to get the CR you want, I like the flat top piston. But there is nothing wrong with a dome if you need it. Make sure the piston has a good cut out near the spark plug, IMO.

A 499 with a flat top piston at zero deck and 68cc heads (5cc valve reliefs) should put the engine just over 13 CR (~13.3). I have run that CR with both 110 octane gasoline and alky.

1993 Daytona, 5.50 at 130mph (1/8) 1.19 sixty ft (PG). Link to 572 B1 - Part 1