I am debating the exact issue! My trans in my AAR is on the fritz (doesn't downshift automatically), so now I'm always rowing that slapstick shifter - I hate it! Although I'd love all the other advantages of the full manual valve body.
Not an issue on a race car, but I getting sick of it for street driving - and I drive stick shift cars! The slapstick to me isn't user friendly (it's too small).
However, I just had a ride in a '70 Dart with a manual valve body and QuarterStick (don't know who makes it) shifter, that was awesome! Too bad it doesn't look stock, otherwise it would be a no brainer.
Very easy to keep the engine on the cam with manual valve body. Especially if you have a peaky powerband.