if you choose other, then post what you use or recommend to get a good work out.

I don't know what the heck a red chair is, but the ab lounge is uber fun! Get the ab lounge!

I agree, the ab lounge is great.

Both are garbage. You're not isolating the abdominals from the psoas attachment with a contraption that does part of the ROM for you.

Janda sit-ups are superior to any ab gimmick. And nothing works your "core" (I hate that term) like balancing hundreds of pounds of iron on your back through squats.