They are quite variable. The briars appear to be bored as standard at about 2.5mm into the bowl which I guess is on the tight side of average by modern standards - the youngest of these pipes is over 20 years old. Some of the older briars are drilled a bit wider. I've never really seen draw as an issue; the drilling is rarely off (I'd contend that's much more important and is the case for all decent factory pipes). The Cherrywood pipes are even more variable. Most are on the slightly tight side of fine; some are quite tight indeed and the very oldest are a bit more prone to high drilling (or have been dug out deeper over the years). They often need to contend with very long stems in cherrywood making cleaning a chore.
I guess that overall they are a bit tight. Certainly in comparison to the wide open, hoover up the furniture, draw I experienced with an MM cob that you guys all seem to take without comment.