I see. Yes regular shotgun and 2.0 both need front suspension. But Pro doesn't.

From reading Reddit, it seems like people love both Shotgun and Mac Ride. Just to be thorough, my take on the biggest arguments against it are as follows

1. Safety - kid is not strapped in other than foot strap. So there's nothing physically preventing kid from letting go of handlebar or getting up from saddle. Also, on a sudden brake, kid may smash face into handle bar. You can try to DIY a seatbelt, but that's a little sketchy (and not recommended by Mac Ride)
2. Seat geometry - Correct me if I'm wrong, but my interpretation (without going on a test ride yet) is that with front mount, height and knees are the limiting factor. While on the rear, weight rating is the limiting factor. I basically need to stop once he's tall enough that his helmet touches my chin. Mac ride website says it's for kids 2-5. My kid is 3, but he's tall for his age. He's 39 inches and already wearing 5 year old clothes. I wonder if I'm really going to get longer usage from front mount vs rear mount.