Seems extremely cheap, but a few cooking blogs I read say they are good. I bought a Chasseur Griddle years ago and it was >$200 so at $15 worth a shot!
Description:
Suitable for all heat sources
Durable 3 layer enamel coating
Griddle includes raised grill bars
Cast Iron Cookware
Cast Iron cookware is durable, practical and beautiful
Cast Iron has excellent heat retention making it perfect for slow cooking
The tight fitting lids retain moisture while cooking which helps keep food warm until you're ready to serve
http://www.aldi.com.au/au/html/offers/offers_20130617.htm
There are dutch ovens, roasting pans etc. too
I have a griddle pan from one of Aldi's previous sale (not quite the same colour but I think it's the same thing) and it's been very good for cooking steak IMO. I'm not professional cook but it has served me well.
I don't see the reason to pay 10X the price for a branded griddle because I think they all do the same thing.