Product review (5 stars): it is EASY. SUPER EASY
After using a local Appliance service to check out my Dishwasher (KitchenAid model # KUDS30IXSS2 ), as it was new to us (recently moved in). The appliance repairman, after confirming nothing was wrong other than a broken top shelf, that "you can pay me $300 to fix, or you can go online & order the parts for half of that".

So ... what are you getting yourself in to with this purchase?

You can NOT simply slide a new track/roller into the existing housing on the top rack (the only thing broken on mine were the 'wheels') - you ARE replacing the entire unit. BUT, it is EASY. SUPER EASY. It took me 30 minutes to figure it all out (instructions aren't incredibly intuitive or helpful, but get the job done), and I honestly think I could replace the other side (wasn't broken ... yet) in 5-10 minutes next time.

I would NOT pay anyone to fix this piece - it is too easy. Spend ~$35 here, and save the other $200. Well worth it, and honestly this replacement part is probably better than the original.