The Mach 1 is a control paddle, while the FORZA is a power paddle. The FORZA weighs 8 oz (14 mm) or 8.2 oz (16 mm), making it heavier than the original Mach 1, which is 7.5 oz (14 mm) or 7.9 oz (16 mm).
The FORZA also has a smaller sweet spot than the Mach 1. Besides that, the specs are almost identical.