I never fitted one as the roof is sensitive enough and prone to failure and I didn't want to risk breaking it!
why would adding an electronic controller to open and close the roof off the remote button or with one tap of the cabin button increase the risk of failure?
I'm onto my second Spider with one fitted now, I wouldn't use the close whilst moving function as motors/rams are fragile but the other functions are useful. So far the only problems I have had were an intermittent hood error light. Dealer struggled to find what was wrong so I looked at the hood system, a lot of it relies upon the deck hatch compressing when the hood closes, it actually bends with the pressure so i cleaned and lubed all the rubber seals on hatch and lower edge of the hood working on the principle dry rubber is stiffer and soft rubber should compress more easily, lubed the mechanism inside the hood, all joints etc using dry lube and it seems to be fine. I do this regularly.
The other one I've noticed is that you can get errors if the battery is going flat, I dont use my car much and over winter it'll sit for a few weeks, at times the battery loses charge and I'd get in and find I had a hood error. If it was in the really cold spell I'd need to warm the interior to get it to close fully, once warm inside the error went.
Actually its probably just luck I happen to have had 2 decent hoods
but I'll continue to look after the seals and linkages just in case it is the reason