So much depends on the resolution of your image but I find product shots such as that will render quickly. Not Keyshot quick but beautiful quality! Maxwell does have Fire which is a fast interactive renderer to help you in setup before committing to your final render. The thing I love in Maxwell is that it's the only renderer I have which often surprises me with it's beauty, others only ever perform as expected or disappoint!

A good speed tip is to use HDRI for illumination, Maxwell handles them very well. You'll be well used to HDRI in Keyshot but in most 3d packages HDRI needs supplementing with actual lights for focused shadows. There are excellent examples of Maxwell scenes lit by a black HDRI with one bright pixel which render with pin sharp shadows. See section 1.5 here:

http://www.maxwellrender.com/forum/viewtopic.php?f=97&t=32630