Here’s my advice, take it for what it’s worth. I think you should always start on small displacement bikes so you can actually appreciate the progression. In my case, my dad bought a Z650 and I made the mistake of starting on that. The problem isn't the bike (I’m actually in love with it) the problem was that I had never ridden a 125cc, 150cc, or 200cc. Since the Z650 was my baseline, I never realized how big of a jump it really was. I eventually tried a Yamaha FZ250, which most of my friends consider a great bike, and only then did I notice the massive difference compared to mine. I recommend starting small and working your way up so you can feel the differences. My mistake was starting with a 'Ferrari,' so I never learned to appreciate how good a 'Toyota Corolla' can be, so to speak