The Natural Philosopher wrote:

Why? SDS is only how the bit is held in, it says nothing about the power
of the drill, its hammer action, or the quality of the bit being used,

Have you ever seen a SDS drill that does not also have the enhanced
pnumatic hammer action that the world has come to associate with "SDS"?

all of which seem rather more relevant than three letter painted on the
side of the drill casing...

I have found the BIT quality to be the key thing, followed by a good
hammer action. You need to smash through embedded flints. This takes
more than a run of the mill masonry bit.

With a conventional hammer drill, you are right - a good bit can make
the difference between a hole in a wall and a small dent plus lots of
swearing. With SDS drills however I have found you are going to get a
hole almost regardless of what you stick in the end!

--
Cheers,

John.

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