Hi Robin,
I have a stack-pack and lazy-jacks on my 235. I would not be without them now.
I sail mainly on my own, and being everso slightly old, I need all the help I can get. The batons, mainly the top baton does snag particularly if I am not pointing directly into wind, but if it does, a tug on the sail soon clears it.
The main benefit, of course is when dropping the sails, which can be a performance if you are on your own or shorthanded, but made simple with this arrangement. I have attached a line to the top reefing lug (if that is the right term) led back to the cockpit which helps lower the sail if I am not directly into wind; so a combination of that and using the reefing lines makes lowering the sail dead easy. There may be 6 ft or so of sail left, but this is very easy to rectify.
Before setting off, by the way, I pull the reefing lines right out which can then rest in the stack-pack, out of the way until the sail goes up.
You mention slackening-off. I never do any of this as I am not sure there is any need! The stack-pack is not in the way and is there ready should I need to reef quickly.
Like Fred. I have also attached the top of the lazy-jacks to the spreaders – gives you a bit more ‘free space’ when the sail is going up so also helps to alleviate snagging.
Highly recommended for an ‘easy life’.
Hope this helps