features for a tiller in my mind are: 1. ability to offset the tiller, 2. tiller weight(heavry enough to break sod but light enough to lift, 3. good manual that actually is readable to you, 4. location of oil or grease ports, number of tines per set(the more the better), 5. service available when you break it 6. slip cutch if you can afford it(more maintance) 7. sized for your tractor so you can till under full power for a good till job.
Dan L