I don't have them on my Rib, but my previous hard boat which was about 8m had hydrolic ones fitted.
I found that deploying them ( lowering the nose and raising the stern) in a bit of a chop really smoothed out the ride, but took a few knots off the speed.
I'm not sure how good they would be on an 8m Rib
I had a terrible experience with mine on the way back from Ribex last Friday.
I have auto adjusting trim tabs fitted to the back of my Gemini and because they were adjusted right down and we were in a following sea the boat kept stuffing its bow through wave soaking us to the skin. We couldn't do more than 15 knots and were ploughing through the waves in a terrible way.
The journey that took an hour in the morning took over 2 on the way home.
I'v never noticed this before because I've not taken Galaxsea out in a sea like that and once she is in the water they can't be adjusted.
I've since adjusted them back as far as they will go but I'm toying with the idea of removing them altogether and using the normal trim only.
In a head sea they are great and the boat requires minimal trim to level her out but last friday was a bad experience that I don't want to repeat.
Be very careful what you choose to fit.
I would go for manually adjusting trim tabs so that you will be able to back them right off from inside the rib if you need to.
Trim tabs are not essential but they do give you the ability to to fine tune the boat for a more comfortable ride, or more speed, or both. Even with an outboard. Please see my reply to your post in the Prosport ribs thread.
If your budget allows, I would recommend you have them fitted.
