Product review (5 stars): Get the 120 caps combo
I just installed this so I am not sure how it will hold up, but wanted to let buyers know the following:

1.  This glue dries extremely fast.  You need to be ready to work fast as the glue will start to dry (even in the bottle) as soon as you open it. Someone above gave a nice tip to keep the applicator in the bottle between each use.  That helped.  The fast drying quality of the glue has much more positives than negatives. Multiple coats and less mess.

2.  I bought this to repair a few rusted prongs, but once you get started, you will want to go ahead and cap the rest of the un-rusted prongs too.  You should do this as the glue will be unusable due to its fast drying soon after you open it up. I doubt this stuff would still be liquid if I closed it and tried to use again later.  80 caps would be enough to repair one rack if you only put caps on the top prongs.  But if you are like me, I wanted to cap the lower horizontal prongs that had a lot of rust.  That made me fall short on a few upper prongs that showed no sign of rust.

3.  I have a nasty headache after applying this stuff.  Lot's of fumes.  I am sure I will live, but like the instructions say, I would stay away from kids with this stuff.

If this holds up, I would definitely recommend it.