Cashel Crusader fly masks are also a good choice. They have a variety of different styles and sizes to choose from. With ears or without, long nose or not, etc... The long nose style is a good choice if your horse has a pink nose that sunburns easily. They also make a fly mask for riding, which is really nice if you do a lot of hacking out/trail riding and your horse is really bothered by the flies. It's called the Cashel Quiet Ride fly mask. It is a lighter mesh material and it comes in all the same sizes and styles as the Cashel Crusader fly mask.
I have a Defender mask (well my horse does, lol), and I (we) love it! She has been using it about 2 years, with no issues. It came with her when I bought her, and its awesome, it was a recommended brand by our trainer. I have felt other brands in stores- the Cashel, etc, and none of them felt as sturdy in the mesh as the Defender does. She did rip an ear in the past, which I just doctored up and it is fine! Will totally stick to this brand when I need any in the future, as nothing lasts forever!
Oh- and she also wears it 24/7, as she likes to rub her face on the wood hay bins in her pasture when her face itches from the bugs- it has fully held up to this practice and kept her face from being rubbed too!