I think the reason why people discourage or are discouraged about rebuilding
these cylinders is because to do it correctly you have to hone out the
cylinder and by the time you buy the hone and the rebuild kit you could've
bought a new cylinder.  And how many times in your life are you going to use
the cylinder hone?  There is a difference between saving money and just being
cheap.  Saving money means that you look at the big picture and see that your
time is even more valuable than the difference in cost of rebuilding something
yourself and having someone else rebuild it for you.  Being cheap is bragging
to others how you saved $20 on a slave cylinder and not telling them about the
four hours to it you to do it or how it didn't work right the first time you
put it back together and you had to take it back apart a few times to get it
right.  This is what they call false economy.
So if you already have the equipment and have done these rebuilds before then
I say go for it.  But if you are a novice please just stick with the new "bolt
on" stuff.  Rebuilding comes later.
My 2 cents.
Ken Wilford
Van-Again
John 3:16