Here's a test I have in process.  I bought an old $5 closeout domain from Godaddy TDname expired auction.  I put a quick minisite up and linked to it with a crazy anchor text phrase.  The domain is ranking for that crazy term now.  It's gone through one pagerank update and I'm waiting for a second to come.  Then I'll redirect the domain to another minisite.  I suspect the second site won't rank for the anhor text, but we'll see.  
This is not the case at GoDaddy Auctions, however. There, GoDaddy starts the auction before the domain names has fully expired and the registrant does have the ability to pay a one-time restoration fee to restore ownership. This is particularly frustrating to those bidding in the auction, as you may be the winning bidder and pay your winning bid price only to find out a few days later that it was restored. You then have to wait for a refund from GoDaddy.
I've seen some people comment about losing the link value of domains that have expired and picked up, but what about non-expired domains?  Let's say a competitor is going out of business and they still have a year or two left, and we buy their domain and site.  Is there a risk changing registrant info and registrars, even if I keep their site up and mostly the same as before?  I was under the impression that I'd want to keep it under their name so as not to hit the uber-reset button on the domain's inbound link value.

When you are searching for the expired domain which you might consider buying, you can conduct expired domains search and learn how to buy expired domains. Or you can take an easier route and go to from your browser’s search bar. Once you are on the site, click on the ‘Free SEO Tools’ icon. Scroll down the list of free SEO tools icons till you come to ‘Expired Domains Tool’ icon.
Page authority ranking criteria are similar to domain authority. It’s ranked on a scale of 1 to 100. Page Authority measures the predictive ranking of a web page. The page authority of a website can change depending on various metrics. Search engines examine the relevance and authority of a page based on its contents and external links. If a webpage has links to higher authority sites and has keywords in it, its authority ranking will increase.
The great thing about this is that it’s kind of like a metasearch engine for all the places that you can find expired domains around the web. First, let’s look at deleted domains. Okay? To do that, you go click on the deleted domains button here and then click on any top level domain that you want to get. I prefer .com because it’s obviously the most common top level domain.

We do not only have Expired Domains, but you can also find lists of Deleted Domains for a lot of TLDs. Deleted Domains or Dropped Domains are available for registration and can be picked up for just the normal regfee at your preferred domain registrar! All Domains have the typical SEO relevant data, like Number of Backlinks, Birth Date and a lot more.