Sounds like a horrible experience. I've recently purchased the Grainfather G70V2 and have been loving it. Recently brewed up 60L of English Pale Ale with about 12 oz of hops and it handled it without issue. Could be the overall size of the unit is helping but the pump on the unit in combination...

I'd agree with Craigerrr. Some craft breweries might have some old sleeved cans from discontinued SKUs etc that they might be willing to sell. I don't know the legalities around it though.