If you're looking for real protective, then I'd recommend Gator gigbags from Yamaha. I sold mine recently, though. They retail for $59.90 or somewhere around there at Yamaha, excellent value considering how thick the padding is. Truth be told, I haven't come across a more protective gigbag.
I am very sure the Mono gig-bags from Citymusic offer better protection than the aforementioned ones from Gator.
However, it will certainly be more expensive, so the Gators might be more value for money.
Just head down to both places and check them out yourself.