Master's degree an advantage or a disadvantage

[Yourself]

If your country has only 3-year bachelor's degrees, is having a Master's degree with a research component an advantage or a disadvantage?
I heard that some departments do not want to accept 3-year bachelor's degrees unless the applicant is outstanding. Of course having one less year to gain research experience is a disadvantage.
On the other hand, I also heard that admissions committees may have much higher standards for applicants with a Master's degree.
Which effect is the most important?

[TakeruK]

I definitely think that having a Masters degree if you have a 3 year Bachelor's degree is a good idea. As you said, a student in a 3 year program has a lot fewer chances to gain research experience, take courses, and make strong connections with professors.

Having a Masters degree might subject you to "higher standards" only in the sense that if you perform poorly in the Masters program, then it is a sign that you might not be able to make it in a PhD program. But, if you do well in the Masters program, then it will definitely help you overall.