Not at all, in my opinion.
I do like heavy strings though and really don't get on with your average 45-100 rounds, especially when gigging when the old adrenaline kicks in. I had a set on my Yamaha BEX4 but took them off in the end as I was using it as a gig back up and they were too slack feeling for me. I'd say they'd probably be a fair match to an average 45-100 bronze string, possibly lighter feeling. They are quite slippery which I like, they have a very glossy wrap.