This is one of the hardest questions to answer for some of the reasons stated already. Many of the posts made already said some very good things to consider, but no one post said it all. There are just SOOOOO many variables involved. And it isn't right for anyone to tell someone else what is right for another person to do. But everyone can share their own thoughts on what they would do for their own herd.
A breeder should have a good pedigree to be used. But that said if all you want is shooters and don't want to sell any of your extra does then who cares if he has a good pedigree or not. As long as he throws good shooter bucks. (Liveoak more or less said the same thing)
Not everyone has the means (dollars wise) to own a "high quality" breeder. And not everyone has the desire to have those sleepless nights thinking about whether or not your big buck in the pen outside is safe.
For some with the money to buy a high quality breeder such as a Rolex, Maxbo, Big Guy, PA Geronimo, Highroller, that works for them.
And then they have to have to emotional strength to house a buck worth that much money.
I personally could NEVER pay the kind of money it takes to have one of those bucks. Heck I could never have spent the kind of money to get the buck I have now. I had to breed my way into him to get one like I have now. (NOT SAYING MINE IS ON THE SAME LEVEL AS THE BUCKS I MENTIONED ABOVE) Now I have to find out if I have the emotional strength to house him everyday
But like Nick says only stated a little differently. Not everyone can or wants to do A/I. Some Amish can't do A/I. Some farms don't have the facilities to do A/I as easy as others can. Some just don't want to get into that aspect of the industry. And that is fine, but they then need to have a breeder buck. Now the questions are, how much can they spend?
If they can't "spend" the money on one, what is the biggest buck they have on the property?
Are they after just shooters or do they want to sell the extra does?
How does the buck the person has produce?
I have always said a quality breeder is a buck that throws sons bigger than himself. If a 300" buck only throws 180" sons he should be shot. If a 180" buck throws 200" or 230" sons that look good, he is a breeder buck.
I have always said if you want to sell your extra does then you need a breeder buck with a good pedigree. And to be honest he better have a good look also.
I stay away from anything with 4x4 mainframes. Don't care how big, that is just my opinion.
On my farm that buck is a shooter, but he isn't on my farm. My farm has a set of goals established and those goals aren't the same as some other farms. So each farm has to decide what is right for them.