Yes and no.
There have been a number of studies done that show "attractive" people tend to be more successful in sales (and other areas) than non-attractive people, where their other qualities are similar. Some examples:
Should You Hire Attractive Salespeople?
Attractive People Are Simply More Successful
Attractive People Are More Successful. Really?
Sales involves several skills (organization, communication, socialization, etc.), and you need to possess at least average qualities/skills in those areas to make a living, and be above average to really exceed.
A highly attractive woman who posses no real sales skills will not (over time) likely outsell a sales-savvy man who is not visually appealing. But a highly attractive woman who possess only average skills may outsell an unattractive man who has above-average sales skills, as her attractiveness will lend some influence.
In the security industry, there are relatively few women in general, and only a subset of those women in the industry are in sales roles (vs. marketing, product management, etc.). The relative scarcity of women in security in outside sales gives them (IMO) an additional boost to their attractiveness factor simply because they are a rarity. Technically, a woman probably only needs to be of "average" attractiveness overall to standout as "very attractive" in the security industry, given that she will be compared to a bunch of mean who are often of a less-than-optimal physique, and not exactly fashion plates either.
On the flip side, an "attractive" man who has above average sales skills will likely outsell the "average" female with average skills over time.
In essence, good looks can help open doors, but you still need to do the actual job of sales to truly succeed and have a definite advantage.