I changed from galvanized to a plastic bodied barrow and have to say it's outlasted 2 galv ones already
(we do shovel lots of sh*t though
I got it from Harbro and think it was £20.
I got a completely plastic barrow from Costco (it was more expensive at £45) and had more capacity - used it for moving straw and piglets (they couldn't jump out) but the base was weak, and it burst when we were loading logs into it
A horsey friend has one of the oversized ones and swears by it, but pig poo weighs more than horse poo and I don't think I'd be able to manoeuvre it very easily
Oh and if you're looking for a shovel for mucking out, I have to recommend the Costco snow shovels, they're about £20, plastic with a metal 'blade' on the edge. They really work well and the handle is long and very comfy to use
I've got one that I've had for 5 years (it's moved at least 44 tonnes of poo in that time and plenty snow too!) and still going strong.