fire risk!
I used the fablon stuff on a baby changing table it was fine,but the problems will be-
its quite expensive per meter,
difficult to do a long run of it(bubbles),
most important, i imagine that stuff will burn quickly, and produce very toxic smoke, the last thing you need in a kitchen. if you want to go ahead, check with the fire department where you live about what they think about the idea.
I heard about it dropping off kitchen cupboard doors because of the humidity in the kitchen,(boiling pans,kettle).
you might have problems with it getting wet, and pealing and looking nasty, (and making your house a fire risk.)
I tried to think of better suggestions but no ideas.
best solution is replacing the worktops, can you charm the landlord? they might be happy to get rid of the worktops if they are gross, because it will put off potential tenants in the future. they might be happier still if you foot some of the cost and sort out someone decent to fit them. I know it sounds a waste of money because its not your house, but you are already prepared to spend good money on something to cover them up, why not just get rid of them?