@Paul_B I have direct experience here so hope I can help.
For perspective I had an orange Foinaven smock. It was a medium but was adjusted to have large length arms and body length. Side zips added. This was all easily achieved with a few phone calls. A pleasurable company to deal with.
Unlike yourself I came across from years of Buffalo use. I am a hillwalker. I climb the Munro's summer and winter, long distance multi day walks and walk the dog. I figured the Foinaven would have been the one smock to cover all of this. My preference is smock over jacket.
When it arrived it fitted excellently. It was an item of great quality. You could tell that it would not let you down on the hill. A robust, professional use garment.
The first outing for it was a typical West of Scotland day in late October. Strong winds and lashing rain. Location, Glencoe.
The walk in was dry and it was too warm for the Foinaven, even fully vented. It was put in my bergen. It was not as 'squashy' as a Buffalo. So took up more room. Not an issue for me as I had space, note it was heavier than a Buffalo. Special 6 for reference.
It went back on as required until at the summit it was fully battened down. Honestly, no issues with hem cords etc. They worked extremely efficiently to close the smock down. Very robust too, no chance of failure. Good size that could be operated with gloves on and cold wet hands.
This is when I started to have my issues with it. Please note the smock was in no way at fault. It worked exactly as intended. Just not to my taste.
The rain was driving. Considering wind chill it was around minus 18 at the summit. I had a Brynje winter vest on below. Nothing else.
The properties of the ventile mean that as it gets wet, the fibres close up. I understood this prior to purchase. Practically on the hill though this combined with the cold translates to the jacket going very stiff. Like cardboard whilst being worn. It was an odd sensation. Not one I particularly liked or could get use to. As the altitude decreased coming down and the wind was less in the glens with a higher temperature the smock became less stiff. The fabric loosened off but was cold though where it touched my base layer when moving on areas it hadn't for a while, it gave the sensation of letting in water. I stopped to checked. Totally dry. No rain water, no condensation. A totally nice warm environment. The wetting out sensation I could never get use to. It never let in once though. I don't think it ever would if maintained properley.
I used it three times, every time in this sort of weather. As a smock to keep me dry, no arguments. Performed faultlessly. I could not get use to the stiffness when cold and wet. The apparent wetting out feeling when the stiffening was subsiding.
The issue that prompted me to sell it though was I had wore it 3 times in inclement weather with a bergen weighing around 8kg. All contact points of the bergen, shoulder/hip straps etc the ventile was losing colour. You could see white patches. As explained earlier, this was to be a multi use jacket. It was beginning to look old after 3 uses. I didn't want to go on a dog walk to a cafe for a tea and cake with a jacket that looked worn. Not with the amount of money I spent on it.
I sold it. Moved to Paramo for the first time. Absolutely loved it. The ventilation, the softness, the attention to detail. I had a Velez evolution hybrid smock then an Enduro jacket. Could fault neither apart from maintenance. I used the garments in inclement conditions. I had to reproof every 3rd wear to be confident of 100% performance. I sold them for this reason.
I'm now back at Buffalo. I'm glad I tried other systems, but for me as an individual. I'm a Buffalo fan.
Hope this helps. Any questions, fire away.
