There was a thread this spring with a bunch of pictures etc on using a boom kicker on a 26S with the pop top up 1/2 way. See if you can find this by searching. The attached picture doesn't show the details (which are on the thread mentioned) but in the picture, the pop top is 1/2 way up and both a boom kicker and vang are in place. This is how the boat was setup for 5 days on our recent trip - except for one evening when I put the pop top down because of high winds. I like this setup because the boat is always ready to sail - just raise the sails - dont have to mess with either the vang or the boom kicker.
The boom kicker has the same exact issue with interference as a boom vang does on this boat. If you dont use a vang, the boom kicker adds extra hassle. But if you do always use a vang (I like having a vang, it is always installed), the boom kicker really adds no hassle.
I use it to keep the boom up when reefing. The only reason I have it is that I don't want to deal with two lines off the top of the mast when I'm setting up the mast as I have enough trouble with tangles on just the single backstay. This was more important to me the first year I owned this boat when I probably set the mast up over 20 times. Seems after four years of owning this boat, Im setting up the mast less now so the tangle issue is also becoming less important.
I think its another one of those "preference calls", between a boom kicker and a topping lift. I'm happy with my setup - but I think I would also be happy with a topping lift.. I do think you need to have one or the other for reefing the main. Even with the boom kicker, I still have a "pig tail" off the back stay for holding up the boom when the sail is in the bag - as mentioned, I only use the boom kicker for reefing the main.