We've had this harness for about a month and a half and I think it's great.
It's fits really well and seems comfortable for Ella. It's really easy to quickly snap a lead on and off the back attachment, which is really helpful as I'm frequently putting Ella on and off lead (sneaky off lead walking where we're not supposed to - hence the quick clip on lead when we see people coming).
I was really unhappy with how Ella's lead was hanging from her collar and affecting the way that she walked with her front legs. I know nothing is perfect but her gait seems more natural when the lead is attached to the back of the harness.
I've attached the lead to the front on two occasions over the past month and a half. It has most definitely given me the extra control needed. However, as with every front attaching harness I've tried, it does pull around to the side and it does significantly affect her gait (hence the extra control). I wouldn't recommend it for a whole walk or for long term use but, for the odd looney moment - it's great.
