I use a sandisk in 64, 32, and 16 gigs. Each one has a specific use, and all work great.

http://www.newegg.com/Product/Product.aspx?Item=N82E16820171610

This is the 64gig I use. I have it full to the gills, and use it when doing more freeform improv stuff. It holds a ton of audio. The 32gig card I use for selected yet still wide range of audio for improv sets. The 16gig I use for very selective audio, usually designed or chosen for a specific type of set.

Never had any issues.