I have just finished a small project painting the woodwork on a flight of stairs. This included the hall under-stairs cupboard panels and flat banister uprights.
I used the Helmi primer and that went to 7 coats, yes SEVEN coats to achieve the finish I desired. I then used two coats of Helmi 10 and the result was excellent. I know this is nothing new but I used a paint pad and some local professional decorators said I was “bodging it”. I know one of them and the other was his friend. Was I bothered? Was I hell!
I used the pads from here Pro Paint Pad and I found them to be very good. They are foam backed which can be an issue if you push hard, the loaded paint can squeeze out. With that it mind I went with the little and often approach and it worked well. You can get the paint on fast and smooth with very little effort.
Obviously I am not a pro but I do care about obtaining a good finish and doing the job properly. I am not sure about larger areas like walls but I may give it a try in a small room I need to complete as it is only 2.5m x 3m
You may want to try them