I've got two of the Kings (4WD super centre) ones, a double for me and SWIMBO, and a king single for #1 daughter.
The king single I think is pretty good value for money. It's cheap, but seems to work pretty well.
The double, that has the centre ridge pole, needed some tweaking to get it right. The hoop poles are flimsy and I doubt they would stand up to any mishaps. I replaced them with some fibreglass ones ($15 from BCF) which fixed that. Even with everything tensioned up, I couldn't get rid of the sag in the guts of the tent. I've added 2 extra guy ropes to the end hoops, and that fixed the issue pretty well.
Overall, the Kings $180 double swag is generally OK (once modified), the mattress is reasonable, the zips are usable (but not heavy duty), and (so far) they don't leak.
For me, I can live with the slightly inferior product because on a cost V's use ratio, it stacked up for me. If I was looking for a swag that was going to see regular use and abuse, I'd look for something a bit more robust.