The overdrive will open up a whole new world with slightly better fuel burn and the long legs for the long trips.
I find my overdrive changes striaght into overdrive very well and quickly with the syncros working well.
Going from overdrive back to direct drive is a slower process with the syncros still working well , but a bit of time is needed to let the shift go though.
My detent ball adjustment on the overdrive could need to be slacken off a bit to free things up.
I find in practice around town I dont bother with the overdrive and only use it in 4th gear only after I get the old girl rolling along a flat open bit of highway.
When in overdrive I tend to leave it in long as possible and let the vehicle find its own speed up and down the hills( unless garrycol is behind me....then I will open the old girl up and try to demoralise him in his 101).

