What do you want to do with it? It makes a big difference. As does the local geology in some cases.
For bigger holes, up to about an inch in diameter and usually vertically down into concrete, I have an older brushed 36V Makita (2 x 18V). It often gets used before there is mains power on site and it gets the job done ok, but I'll run out a cable and use a corded tool for big holes if the option is there.
For little holes, up to about 17mm and often into brick, the 18V brushless DHR171 is pretty close to ideal (I think it's the XRH06B in the USA). It's lightweight and easy to handle overhead or up a ladder.
With brick-built houses, using a too-powerful SDS drill just smashes the backs out of bricks once you get half way through. It seems to be more of a problem with harder bricks, which is where the local geology comes in, even if you are not drilling into the local stone.
They are very different machines for very different jobs. All of the big names offer a similar range of SDS drills and I've not used enough of them to regard any one as "the best". None of the real tool manufacturers seems to make bad ones.
It's a case of choosing the one that best suits your needs. Usually, the battery platform will be your first factor, then look at the range to see which of the drills that use the battery is best suited to your use. Narrow it down to 2 or 3 and look for reviews. Read the reviews, rather than just looking for the highest star rating. See what folk *with similar requirements to you* think of them: in my case, someone with the 36V Makita and fitting curtains for a living would probably post a lousy review: it's not that there's anything wrong with the drill, just that it's not the right choice for their job. Likewise, someone installing crash-barriers would probably post a lousy review of the DHR171.
I don't need to worry about dust, etc, but for those who do, the vacuum system can be the most important part.