I would say ACE screen is not the best visible as I ride towards the Sun but it could be also caused by my photochromic glasses

Still, I can see everything I need to see on the screen. Garmin users also complain a little for the direct sunlight visibility.
Anecdotally, Wahoo 2 screen is better visible under direct sunlight conditions than the version 3; and Garmin -30 has a better visible screen that the -40 or -50 (it is what either I could observe myself or what Garmin users told me). This is the price paid for gorgeously colourful screens! My brother who uses a Garmin 530 got a slightly damaged 540 from me as a gift. After he replaced the screen on the 540, he refused using it because of "poor visibility in the sunlight"!
According to my own observations, the way Wahoo navigates you is a way better than I could ever achieve on a Garmin. The course is a solid red line with occasional arrows on Garmin while it is a continuous series of black arrows, turning green for climbs or to blue for re-routing on Wahoo. Regarding the re-routing, Wahoo really aces it, which is not that good for Garmin.
It is all down to what Vado you own. If it is an SL, Wahoo is the only computer to report the Range Extender. Also, Wahoo displays OFF, ECO, SPORT, TURBO, MICRO and SMART while Garmin shows meaningless and confusing numbers for Assist Mode.
I'm setting off for rides this Saturday and Sunday. Sunday's going to be a sunny day. If you're patient, I'll bring some photos of the ACE screen from actual rides.