Product review (5 stars): This Whirlpool metal part kit is well worth the extra $10
Just installed on my KitchenAid KUDS30FXBL1.  It took 15 minutes tops and everything had a quality fit and finish.  Even though this is a Whirlpool kit, it fits the KitchenAid too.  Whirlpool is a common manufacturer for most (or all?) U.S. made dishwashers.  I almost bought one of the alll-plastic kits, but read they would only last a year or two, and  I'm not interested in short term repairs.  I ran across this kit that has metal parts where it counts and I expect it to last for 10 years.  The instructions were decent, although the photos were a little dark and hard to see.  But kudos to Whirlpool for including instructions!  I read that some of the cheaper plastic kits don't.  If you can't figure it out, there's a very detailed 14 minute YouTube video that covers how to remove the old parts and install the new: https://youtu.be/otUn8eoceBw . You'll spend about $10 more on this kit than the plastic kits - and it's well worth it.

FYI - I ordered this from another reseller on Prime (don't recall who), but after 3 days it hadn't shipped.  I worked with an Amazon agent to cancel the original order and re-order from Free_Shipping_LLC.  Amazon covered the costs for overnight shipping.  This second order also didn't ship on time, but did ship a day later.  Both orders said "in stock" when placing the order.  I recommend verifying your order ships on time instead of waiting 3 days like I did.