I put a reactor 40 in my 228. I have mixed feelings about it. When it works, it is *awesome*, one of the best upgrades I've done.
OK, so the downsides. Don't get shadow drive unless you have power steering. Shadow drive shuts off the auto pilot when it thinks you are steering. I don't have power steering, my power comes from the steering wheel. Which is tight, I found the nut on the engine that controls how stiff things are. If I loosen that enough that steering is easy, well, the currents, wind, whatever that pushes the engine around, shadow drive thinks I'm steering when I am not. That's a little bit annoying.
The biggest annoying thing about Garmin auto pilot is it loses it's mind a bunch. If you set a course and 30 seconds later engage the autopilot, or you set a course and you are not 99% on that course, when you engage the autopilot it will swing the boat to get on course and then go way past the course. That part of Garmin sucks.
So what do I do? Most of the time I'm on heading hold, that works fine. When I want to go to a waypoint (crabbing) or wherever, I set the course but then before I engage auto pilot, I get the boat up to speed and get on the line, then engage.
I love my autopilot, it is like having 80% of a deck hand on board, but I'm realistic about what it can do. If I were to do it all over again, I'd research who has the best auto pilot, does it work with Garmin, maybe I'd get something else.
Oh, another thing I love about it is pattern steering. When running a lot of lines out back, you need to do a perfect half circle, it will do it.
The other thing I'd say is get the dedicated display.
