I've used both and would incorporate both in training. The focus on core strength and stability in both systems is incredible . The Rip trainer allows you to explore more range of motions and is safe for all levels even those in wheelchairs can benefit from its use. The TRX trainer allows you to engage the same muscle groups and more in that you can advance to levels of bar calisthenics with how the system is created . All in all I recommend both systems . You will benefit wonderfully!
I use the TRX for all levels and abilities of fitness. Both systems provide a terrific core and strength workout while using ones own body weight. I opted for the TRX for my studio and create the Rip trainer effect with Pilates equipment that I own.