Shimano 600 / ultegra quill stem

any thoughts/experiences with the shimano 600 / ultegra quill stem? I have never used one before (or the identical dura ace) but I am considering purchasing one to match my other shimano components -- just wondering if the hidden bolt system is reliable and if the stem is not likely to fail.

my dad has been using one for the last 15 years with no problems.
well except that as he gets older and less flexible the stem now is too long and low. which means - i'mageddit!

edit:
actually. what size allen key fits the hidden bolts?

6mm

any thoughts/experiences with the shimano 600 / ultegra quill stem? I have never used one before (or the identical dura ace) but I am considering purchasing one to match my other shimano components -- just wondering if the hidden bolt system is reliable and if the stem is not likely to fail.

i've got a DA and a 600 one...
as quoted earlier a 6mm a/k does the job has to be a long one though to reach the end.
i've had no problems with them and they're god knows how old and still going strong.

Used a DA one briefly, don't overtighten the cap, or you'll shred the threads.

...a 6mm a/k does the job has to be a long one though to reach the end.
I use a normal length one the wrong way round (i.e. insert the long end of the key), then use a ring spanner on the short end to turn it.

thanks for the info everyone.