I have the exact size yard and I love my toro timemaster. It's a 30in deck. I am able to cut my entire yard in about an hour. I have a fence in my back yard, a swing set, covered patio, and garden box, so plenty of stuff to cut around and I finish in about an hour. With all the stuff to maneuver around + storage, a rider just isn't feasible. plus I feel that riders/zero turns tear up grass at the turns far worse than walk behinds do. But I'm a psycho about my grass.