I agree in that the different brands share a lot of components, so I would suggest it comes down to operator comfort. Does brand "X" offer more leg room, better seat, back support, ease of getting on and off, smoother ride, tighter turning radius, are the controls laid out for ease of use, is the mower deck heavy to lift? And these factors will be different from person to person, so there is no single correct answer. A tall left handed person will most likely feel more comfortable on a different machine than a short right handed person. I'd also be aware of where I would be able to get parts and service from, is there a reliable dealer nearby? That's how I would shop for an entry level machine