Product review (3 stars): Right size, easy fit, but ...
After my washing machine tub stopped spinning in my Kenmore 90 Series, I noticed a small black pile of debris.  Some quick internet research told me that my 20 year old drive coupler had disintegrated.  Order this part, watched a YouTube video, and had the machine up and running again in 2 hours.  Just to be fair, the part replacement took about 30 minutes, the other 90 were spent cleaning 20 years of accumulated soap residue, dust and dirt out of the unreachable cavities.  Long story short, the part works great!  No, it's not a branded Whirlpool part (mine was made by Jason), but then again, I didn't pay the crazy Whirlpool price, either.  And it did NOT have the new metal insert!

UPDATE 1/15/14:  Well, this part gave 11 months of service at a cost of a few bucks, then shattered on the drive shaft.  Motor and transmission are both spinning freely, so I don't think that's what caused it.  Seems like the plastic was just not of the same quality as the original FSP part that lasted about for two decades.  Can't really complain about the cost, but wasn't excited to spend another hour taking the laundry room apart to work on the washer to replace the broken coupler, not to mention the 2-3 days of being without a washer while the part gets here.  Going to buy the Whirlpool FSP part this time ...