Product review (4 stars): Much more durable than the factory parts
Bought this to swap out the cheap-o plastic components on my 3-year old dishwasher top rack, which was consistently falling out of the track due having snapped off the little prongs that hold the wheels in place.  This was my second attempt (the first one I bought, the wheels were too small and didn't fit in the track -- my fault for not confirming ahead of time -- but Amazon was great about the RMA).

Instructions really weren't that bad if you follow along and are reasonably spacially inclined.  First side took me about 6 minutes, and the other side less than 2 once I got the hang of it.  The raise/lower motion is very smooth on the metal guides.  The wheels are still plastic, but the interior hub is now solid, so they're not coming off!

It works so well, I'm now upset that Whirlpool didn't just suck it up and spend the extra 1.50 to put this on the original model, instead of the substandard junk they used.  Worth the $40 to upgrade, though!

Overall, I'm very pleased with this.  I took off one star because my kit said it was supposed to come with a star adapter to fit a standard phillips screwdriver, and that was missing.  Seller didn't seem interested in helping about it ("That was our last one, so you'll just have to go find the right type of screwdriver." Gee, thanks.)