I did this a couple weeks ago. I started out with the scoring tool and the spray on gel. Went OK, but there were 2 layers of wallpaper. I was at Home Depot at 5:45AM the next morning to get a steamer for less than $50. That went much better, still used the scoring tool. My approach became, use the steamer to get the bulk off, then sprayed the small remaining pieces, moved on with the steamer, then came back to scape (actually wipe) away the small pieces.
Although this was time consuming the biggest pain about this job was the cleanup. Man what a CONSTANT mess. Clean as you go, then count on a few hours at the end.
I primed the walls afterwards, then applied 2 coats of paint. Looks much better.