I installed the X-5 on my O'Day 30 over a year ago and it has performed perfectly. Several overnight trips and hundreds of miles in the ocean in various conditions.
The installation was very simple and easy.
The only thing I have not been doing is to rinse off the drive unit fresh water after use (guilty...) so the drive was a bit noisy after not being used for a few weeks but now that I have been rinsing it, it is not a problem anymore.
Oops.. Just realized after writing this that you were asking more about upgrade ideas...
Sorry, none here so far.
O'Day 30 - Stuart, FL
Oceanis 411 - South of France