The slant on the mStand is too steep for comfortable use with MacBook Pros, as these machines are crippled in terms of how wide you can open them. When putting my MBP on the mStand, I couldn't open it wide enough to view the screen comfortably, thus rendering the mStand useless for my needs. I purchased a Griffin Elevator which is a higher stand with less "slant" than the mStand and it works better. I think the mStand would work very well with older PowerBooks that can open wide enough to cope with the steep slant on the mStand.