I prefer the Full Contact Fighter Ultimate shorts. They secure great and comfortable and great for both kicking and grappling. I also like the Tapout Shorts but prefer the FCF shorts. I tried a pair of Sprawl shorts and for me I didn't really like them. The legs are not wide enough for me and they just don't feel right. They bind up a bit while kicking so I never train in them.
I personaly like Full Contact Fighter. But it all depnds on what kind of material you find comfortable. If you like the tight spandex go with Wand Fight Gear or Tapout. If you like loose board or long shorts I'd go with Full Contact Fighter or Sprawl