I've been experimenting with Step Sequencer. I would not recommend using it to totally replace PRV, to be honest. It is more suited to 1/2/4 bar repetitive sequences, and not all that useful for writing accompanying melody lines, in my opinion.
I've also been using it to create rhythm/drum sequences. Once I've settled on a basic pattern, I convert it to a straight MIDI track.
A good feature of the Step Sequencer is the ability to stretch out, in track view, the 1/2/4 bar sequence over many bars, and it looks a little bit like a groove clip.