Augmenting on what NiN said…
What you don’t know is anything regarding the Driver Sensitivity, for example. There is a lot more involved behind the scenes than just looking at an Amplifier rating will tell you. Without knowing every aspect of the complete system then (not just Driver Parameters but also Cabinet Size and Port Tune) you can’t even attempt to model it to see what the performance might be.
Rather this is why it is important to see quality resting done and be able to understand what the tests mean. The CEA-2010 Burst test is one but it only paints a limited picture. Long Term Compression Sweeps are another excellent test showing you FR at various output levels and where the whole system starts to break down in terms of maximum output. After that, seeing the distortion components will help you understand how clean the output is.
In short, amplifier wattage is the most useless aspect of subwoofer marketing to attempt to judge anything by.