There is a consistency to cobs, so that you can expect a certain level of performance from just about any of their various incarnations from Freehand and McArthur sized to the Morgan or Eaton and all in between.
The used estate briar is all I've smoked, although I've got lots that are unsmoked.
I'd rather go with a pipe that's all ready broken in. I think each genre offers something of value, be it Meerschaum, Briar, Cob, Cherrywood, Morta, etc.
Lately I've acquired a couple of briars made pre WW11 and found them exceptional.
Just like tobacco, pipes offer variety.
A newbie might have better luck learning with a cob.
Briars probably offer more variety of shapes, weights, and stem materials.
I rotate meers, cobs, briars and even my Ropp Cherrywood, occasionally.
You find preferences for blends in certain pipes, or a tactile experience you might have a yen for at any given moment and having choices is nice too.