Are there any advantages / drawbacks to adding trim tabs to a boat like a 22 / 23' Scarab ? Have read that they help in rough stuff...

I have 110S k-planes on my 22 Scarab. I use them mostly when we ski. When on plane my seems to ride pretty flat. Doug

I'm adding a pair of Victory tabs to a 23 foot Checkmate next week. My plan is they will help provide a better ride in the rough water I often encounter in the Potomac river and Chesapeake Bay. I'm certain I'll at least be able to remain on plane at slower speeds which will help in the really rough stuff and will be safer at night. Additionally, any time getting on plane is easier, it has to be better for your outdrive. As a bonus they might help with my high-speed chine walk but I'm not counting on that. I hope they don't shave off any significant top end though.

Do you find it helps in any other way? I know that it was an option on my boat and was not installed. I was looking for ways to make it a little more stable in big water. My boat tends to knife into waves sideways if I am heading into rough water looking for a way to flatten it out .

I put bennet tabs on my 18' Sutphen, and I think it's the best modification I've done yet! I use them regularly to set the boats level according to the seas I'm in. Much more level and consistant rideWorks great!.
Just make sure you get a good clean installation on the transom, and in the bilge. Also, you'll really want to think about where / how to postion trim tab controls. Most people seem to run them in front of the throttle. But you may or may not have room?

I've got 150K planes and they work great.
24 pantera.
Help keep the boat level in a beam sea or wind coming from an odd angle.

Yea that nose dive at weird angle thing gets scary. If I can correct for that it would be great.

Just to clarify, tabs will not help keep the nose up, they help keep the nose down! If you've got nose down issues, you might want to look at your use of throttle (when cresting waves), or your angle of attack on waves, or maybe you're in waves that are too big for your boat? Safety first!

What kind of prop are you running?

Mirage plus 27P and a Bravo1 26P