Not all of the Go rooms have tubs. Some only have the showers. I believe from previous experience that 'outward' facing rooms have only showers, while the ones facing the garden have both a shower & a tub. (May not be 100%, but has been from my numerous stays - I imagine there are some room locations that may vary).
However FAB I believe all have only the standard bathtub/shower combo you find in most hotels.