Product review (3 stars): Works, but flawed bottle design needs attention and application is a pain
This product does work, and it's the only product I could find that can endure the high temperatures it'll be exposed to in a dishwasher, but I'm rating it three stars for these reasons:
 The bottle's design is flawed
 It is an enormous pain to apply since it's the consistency of cold honey (read below for application tips)

The bottle is supposed to have a washer that sits on top of it when you unscrew the lid, but after using two bottles of the stuff on my old dishwasher rack, I can tell you with a reasonable amount of certainty that all that washer is going to do is get stuck in the top of the bottle.  You can shake it and shake it and do a special dance hoping it'll fall out of the lid, but odds are most people don't even know a washer is supposed to be there.  This washer is crucial for two reasons: A) It scrapes excess goop off of the stem when you remove the brush from the bottle B) It significantly extends the life of the product by shielding it from the air.  Because the washer gets stuck in the lid, the product dries out and you're dealing with a frustrating half-dried mess of a product once you're 2/3rds into the bottle.

If you're covering 30-40 spots, one bottle used carefully should last for two coats.  If you have more than that, you'll need two bottles like I did.

Application Tips:
1) Use sandpaper to clean all rust off of your dishwasher.  Don't remove any more plastic than you need to remove.  If the plastic is bloated or needs to be removed, pliers and possibly a metal file might be in order.  Lightly sand the perimeter of the affected area so the product can grip.
2) Clean the metal and surrounding plastic with isopropyl alcohol to remove any remaining rust, dust, or oil from the surface.
3) Shake the bottle hard for a couple of minutes.  There is a ball bearing in there that will help mix the solvent in with the substance you're applying
4) Take a big glob of it and liberally apply it, then spread that glob around, ensuring you overlap it with the existing plastic.  It's much easier to use the glob method than trying to paint on small sections at once, because it just smears it around.  As you're painting, ensure that you circle the metal with the product, even if the spot you're covering is just a single dot of rust.  You want to do this so you form a circle around the metal and the product can be self-supporting vs. trying to cling to old plastic material in a single spot.  For the dish prongs, paint at least an inch down the prong.
5) For your second coat (and you will want a second coat), you don't have to worry about circling the metal a second time.  The product's solvents will soften the top layer of your previous coat enough for it to cling to itself, so you can just paint over only the areas that need thickening, saving you some time/frustration.
6) Let it dry overnight as the instructions dictate.  I waited two days to be sure that the product had fully cured.

It took me hours and hours of work, but I can now use my dishwasher without it putting tons of rust spots on my plates.  I've already run a load of dishes and it looks completely unaffected.  It seems to work great, but man is it a nightmare to apply!  I probably spent 6-8 hours prepping and applying this stuff when it was all said and done.