We found both of these mugs to be excellent! However, our preference is to give you your preference!
The RTIC- Excellent for the on-the-go worker. It has a twist on lid with a snap-down fluid protector which makes the mug spill proof and dust resistant. The handle also provides ease of grasp similar to your everyday coffee mug.
The YETI- Excellent for the office worker. It has a press-press on lid that provides ease of removal and spill resistance. Its size and smooth shape makes it comfortable to hold.
NOTE: Both 20oz mugs are equally superior in keeping your hot things hot and your cold things cold!