Are you saying that oil changes are listed on the Carfax at regular 7.5K (or less) intervals? My understanding, from feedback posted on other forums, is that oil changes rarely show up on a Carfax. But perhaps Mazda is an exception, and does update the data source that Carfax uses for their report. If so, knowing that oil changes were done regularly would be a big plus in any car buying decision.
My daughter's 2011 3i 2.0L is a very solid vehicle, and has had zero issues beyond routine maintenance. That said, any 7 year old vehicle with 160K is very likely to have some problems going forward, and will need either DIY time, or some $$ expenditure if you don't do your own work So if you're willing to live with that, IMO that Mazda is as good or better than anything else in the same age and mileage category.
2011 3i 2.0 A/T 93K miles (daughter's ride which I maintain)