I appreciate the clarification on the differences between the two items.  I have used the Delayed Reaction in the past and really like it.  I went to the Powerhouse website, but cannot seem to find it.  Do you know if this item has been discontinued?  If so, is there another polish on the market that will provide the same benefits as the Delayed Reaction?

No.
Delayed Reaction has an additive that clogs the "pores" of resin balls and reduces oil absorption, one of the major reasons that they hook the way they do. It reduces the overall hook AND it reduces the backend, when polishing the ball.

Extender polish has a very fine abrasive additive that makes the finish even finer. It adds length and increases the backend more than regular polishes does.  The amount of length added depends on both the grit level at which the ball is sanded before polishing and the amount of polish, the amount of pressure and thetime spent on the spinner.

If you're speed dominant and need polish, regular polish or Extender can be useful.

If you're rev dominant and are already bowling on light oil and your polished ball has too much backend foe the amount of dry you are seeing, you  probably need Delayed Reaction.

Regular and EXtender Polish will wear off in time and need re-applying. Delayed Reaction needs to be sanded off to unclog the pores. The polish may wear off in tme, but the pores won't get unclogged with use.