Those car listings are pretty iffy. The Enclave listing had a rear crankshaft oil seal replaced at under 5k miles. The car was serviced at only 400 miles after buying, which could mean anything. The rear shock absorber was replaced at 37k miles. The car was serviced again for something 100 miles later at a different shop. Sounds like this specific Enclave was not built with much precision.
The 2013 Acadia SLT-1 is a higher trim than the 2014 Acadia SLE. The 2013 SLT-1 you said had a wierd CarFax, but the website doesn't provide a CarFax. The 2014 SLE doesn't have any maintenance records and only shows that the dealer that is selling it replaced the tires and brakes. Between these two Acadias, the 2013 seems like the better choice.
I know I'm a Toyota fan, but that is only because they are reliable, solid cars. The Highlander rides smooth like the GMs, but has a smoother quieter powertrain, more available features, is not a stereotypical rental car, and is more reliable. I've found some other listings in Sunnyvale that are worth a look. They have good CarFaxes.
2013 Toyota Highlander Plus V6- this guy got his Highlander maintained (oil, filter, normal stuff) every 5k miles. Usually Toyotas are more expensive than GMs, but this has a comparable amount of miles and is pretty well equipped.
2013 Toyota Highlander Plus V6- Very similar to the one mentioned above. Well maintained.
2012 Toyota Highlander 4WD Limited - Also well-maintained, zero accidents. This one is very well-equipped with all the bells and whistles, close to Lexus quality. It has 4WD, navigation, leather, tri-zone auto climate control, JBL sound system, sunroof, power tailgate, bluetooth, push button start with smart key entry, heated seats, dual power seats with driver power lumbar and thigh extension, and the tow package. Slightly higher mileage than the other two, but not significant. The Highlanders last longer than any of its competitor SUVs. This is the best listing and I think you should test drive it. The car is in Burlingame for just under $20k.