I'd go a bit further than that. Since the cited ref supports what -5- reverted to, that text is valid even if you don't like it. If you are going to alter text that is based on a cited source:
Check the source to make sure the text in the article is or isn't supported.
Provide an edit summary as to why you are changing the text.
If your edit is disputed, take it to the talk page.
The edit you made to X-Men: First Class (film) appeared to be capricious, at best. But in conjunction with reverting a spelling correction and filing an unfounded vandalism report against an editor you are edit warring with, speak to bigger problems. Right now I think it would serve you well to read over:
Wikipedia:Vandalism
Wikipedia:Harassment#Wikihounding
Wikipedia:Harassment#User space harassment
Wikipedia:Assume good faith
Wikipedia:Disruptive editing
At the very least.
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