Kenact, I've been using my AEG induction hob for over 5 years. The glass hob can get scratched if you move your pan back and forth during cooking, but that's to be expected. (My glass dining table gets scratched simply through daily use.) The back burner remains pristine because I only boil and simmer in the pan, so no moving it about. I fry on the front burner, so the glass surface is dulled. In the beginning, I used to put a sheet of baking parchment on the cooker, then a frying pan on top. It worked fine and stopped not only scratches but grease splatters. After a few years, I stopped doing that for no reason, as couldn't be bothered!
Oh, the glass will get hot, depending on how long you've been cooking - it's the heat from the pan and contents being absorbed by the glass. (If you put a hot pan on a glass dining table, that will get hot too.) The induction cooker heats the pan only, but that doesn't stop the heat from the pan transferring to the glass. So 'H' comes on the cooker when you switch off to remind you it's HOT.
Induction is more efficient than gas - gas is about 48% energy efficient and induction is 98% approx. Both are instantaneous and depending what I'm heating and the quantity, induction can be faster than a microwave oven. And I never use the power booster mode, so that's saying how fast induction can cook.
I slow cook on the lowest setting on the induction cooker (1 or 2 setting) - makes the tenderest pot roast from the toughest cut.
Hope this helps!