I'm new to the spell. Having only gotten it last night, but I did have a chance to tank and boy did I suck. Had nothing to do with BLU I just haven't gotten used to the skills, but it definitely feels smoother now compared to lvl 50 cap and relying so much on the look and mighty guard. I plan on trying it out more when I get back from work.

I mostly just love the idea and flavor of the spell.
Some weirdo (Martyn) in blue randomly immitating bystanders for kicks. That in itself makes me smile.