The main advantage of the Enclave over alternatives is it has the most passenger and cargo room. It is an old design at this point, though, dating to 2008. I think a complete redesign is coming for 2017. They did revise it a little for 2013, but this also increased the frequency of reported repairs a little (in our stats the 2012 and 2014 are a little more reliable than the 2013). Enclaves older than 2012 have been much less reliable than the 2013 and up in our stats, so it's hard to say how reliable the 2012 and up will be as they age.
I really like how the third-generation (2014 and up) MDX drives. You can find 2014 MDXs in your price range, but not very easily. Do you need all-wheel-drive? If not, one will be easier to find for $32k or less.
Another possibility, though one as old in design and technology as the Buick Enclave, is the Mazda CX-9.
With any car you want to own for eight years, newer is better. A five-year-old car will be 13 at the end of that run, and many cars become less reliable after they turn ten.
I'd thoroughly check out at all three and see which you like best. Let us know what you find!