Bill was asking about my Kato davits, and if he were going to go with Kato, I think my recommendations are sound. I about 15 years learning curve with the Kato Island davits and can only comment on them. I do not have experience with other brands.
With regard to the stabilizer bar getting in the way of swimming, it is high enough that I do not have to duck under it, and, in fact, I use it to hold onto whenever I am on the swim platform or getting off the inflatable onto the swim platform. I also use it jump feet first into the water
. When at anchor with the inflatable launched, I tie two lines from the inflatable to the stabilizer bar. When the inflatable is on the davits, I also run a couple of vertical lines from the inflatable to the stabilizer bar as a backup for the vertical davit lines. I do have to duck to get onto the swim platform when the inflatable is on the davits.The 2 bolts on either side do not secure the stabilizer bar to the davits. There is a hefty triangular shaped metal piece that wrap 180 degrees around about 6" of the ends of the davits and are secured to the stabilizer bar on each side to a ~1/2" nipple that juts out from the top of the stabilizer bar. The stabilizer bar end pieces fit over the nipples on each side and are held in place by 2 hefty SS cotter pins through the middle of the 1/2" nipples. This makes it easy to remove the stabilizer bar from the davits. What I was trying to explain is that if you do not have these 2 bolts extremely tight, the end pieces will move on the stabilizer bar allowing sway. See attached photos.
I agree that the davits should be above the lift points. My inflatable is larger than yours and my lift points are further forward and aft than yours, so my davits are further apart, also directly over the lift points.
My RIB 350 weighs 161 pounds, the Nissan 9.8 weighs 82 pounds, I have two gas tanks weigh about 11 lb each, I have some lines and an anchor, and I often have a kayak stowed on top. So my set up weights probably about 400 lbs. My davits are rated at 300 lb each. If I forget to pull the drain plug, I can come close to the max recommended 600 lb weight.
My inflatable rides very high, and it would be difficult for a wave to board from astern, at least on Lake Ontario. I don't plan to cross the ocean. Lake Ontario is enough for me.
Last time I sailed Boston Harbor we had all we could do to dodge the lobster pots and high speed ferries.
