So, apart from the crest vs coat of arms terminology issue, already addressed by others:
Even under Scottish law, there's nothing to prevent someone from displaying a picture of any coat of arms he wants inside his own house, particularly provided he doesn't misrepresent it as his own. Of course, your profile says you live in Texas, where Lord Lyon's writ doesn't run, so perhaps the question is more usefully addressed in a wider context of good heraldic practice.
Let's start with the misconception that a coat of arms is only for a specific person. It is actually for a specific person, or more rarely persons,
and his descendants in the direct legitimate male line. (I'm simplifying a bit; there can be exceptions, but if they applied in this case you'd already know about it.) Thus, the question is: how do you know that...
You can only know this if you've traced your ancestry with a high degree of certainty to a person who legitimately bore the arms shown by Burke. The crest you give below is the one that goes with the first entry, which fortunately is identified as originating in a specific town and county (Ewdon, Shropshire). The only way to establish a right to use these arms and crest as your own is to do the genealogy.
English mottoes are borne at the discretion of the person using the arms; they're not part of the grant. There are certain mottoes that tend to be used over and over again and might be thought of as family mottoes, but there's nothing formally fixed about them. The situation is different in Scotland, but these arms are English. Which gets to the core point:
A crest encircled by a strap and buckle is indeed a badge, specifically the badge worn by "followers" of the person whose crest is depicted. People who have their own (Scottish) arms do not use a strap and buckle around their crests, because following yourself just takes you around in circles.
In any case, it is a specifically Scottish custom (albeit not a very old one) and makes no sense used with English devices. There is no Clan Masters with a chief for you to follow.
If you identify for some reason with Buchanan, then the thing to do is to wear the Buchanan clansman's badge. But be aware that the whole sept thing is at least as fictitious as the notion that everyone with the same last name is entitled to the same arms. There may have been a family named Masters that was under the protection of or otherwise affiliated with the Buchanans, but that doesn't make everyone named Masters a member of Clan Buchanan. Particularly not the specific Masters family of Ewdon, Shropshire, whose arms you've identified.
Originally Posted by Joseph McMillan
So, apart from the crest vs coat of arms terminology issue, already addressed by others:
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