I really like the flat wound sound on my Series I shorty, but it's not the only way to go. Back in the day, when I had a long scale Series I, I had a problem getting decent low end out of it with rounds, but then I tried some DR Sunbeams. Holy moly! The low end was amazing. They also sound great on the shorty. So, I think it depends a lot on the string. Series basses are a different animal, so it does take some experimentation to get to what might be a previous comfort zone. However, if you start without trying to match previous conceptions, you might find yourself going to some new places only the Series basses go.