So depends on the gig. The 4 with a Hipshot will do most cover gigs, IME. The 5 has 3 lower notes, which I don't tend to use all that much; but there are a few tunes where they can be useful. Detained lower notes on the 4 speak a little better (longer string length), and there are some well known tunes played in that format where the lines lay a little better. OTOH, detuning the E can require a little more fingering preparation. I say go with what works best for you.