Congrats ymurf! I got my 121s in July 2015 & have about 150 hours on it now. I'm in my mid 70's & learning to drive it was challenging, but I managed - - didn't take out any extraneous objects my 1st time out. It's my 1st zero turn. I've learned to wear a set of headphones = = it is pretty loud. I was also surprised at how much debris it stirs up. Anytime your mower deck is running & you are over an area that is not all grass, be prepared to be peppered with debris & dust. Eye protection is needed too. I do like the maneuverability & the speed!
It does enjoy gasoline. Can't tell you the usage per hour, but it's high compared to my previous riding lawnmowers.
On balance, I'm happy I bought it. How could I say no? The 48 month 0% interest was too easy.
Enjoy!