It depends how you ride. If you just take the bike out in warm dry weather and ride in straight lines and go slowly around corners you'll be fine.
If you ride in a sporting manner, or on damp roads then no.
I thought they were ok but I was a little suspicious to see I had ridden them to the edge when I wasn't pushing the bike. I think they have a flatter profile but have yet to compare side by side.
On my second or third ride, once I was comfortable on my new bike they started to slip in corners I never had a problem with before. With plenty of tread still on the Dunlops I got rid of them. There are several online expert reviews that show the tester sliding on them.
Swapping them out with Conti RA3 made a world of difference.
The z900 is sprung for 80 kg. At 108kg oh heck no. Again, if you're just toodleing around you'll be fine.
I'm 84 kg in my undies and just had my bikes suspension rebuilt with .95 springs in the forks and 700 in/lb shock spring. Nice.