I agree with Eddie... If your transmission has delayed shifting into drive and reverse, then you need to fix the Valve Body and/or the sticking Shift Solenoids. Of course there is usually no harm in trying those snake-oil fixes....the only harm is to your wallet...since it is not likely to fix the problem. If by some fluke, it does clear up the shift delay, it will probably only be short lived and will likely return in a few days or weeks.
You can't permanently fix any mechanical problem with something from a bottle. At best, it will only temporarily mask the symptoms for short while.....kind of like kicking the can a little further down the road.
...Rich