Thinking about testing out how much more cooling capacity the 2.08" profile has when actively cooled with 50mm fan(s) vs passive. I would blow the fan down into the fins and have a cover over the top to direct the airflow from the fan through the fins and out the sides of the heatsink bars, like the Alpine 11 but much longer and skinnier. Im going to test 1 50mm fan on a 23" long bar and one without the 50mm fan purely passive cooling, both bars are on one single string on a dimmable driver and I cranked it up to around 50w dissipation (close to 60w on kill-a-watt) the other day and forgot about it for about 20 minutes or so and the bars were pretty warm kinda hot but not burning hot either. Still too hot for my liking, trying to test out different theories before I do my next build, still the plan is 35x Vero 10s plus reds/blue most likely just the ones I already have made they seem to put out plenty of extra red for my little tent.
Anyway Im working out the heatsink part of the equation, if I didnt care about spending a lot I would just get the 3.5" profile but thats overkill and could be good for passive cooling my intended setup but I am a cheap ass and passive cooling is much more effective allowing the use of less aluminum (cheaper). If the 50mm fan test goes pretty well on the 23" bar of my veg light then I will try 2x 50mm on 32" long bars with 7 Vero 10s each @ ~200-215mA each (max).
Sorry if everyone getting sick of me rambling about my testings for a new build but figure its relevant if the 50mm fans work well on the 2.08" profile it could possibly be helpful to others too. Im not going to have hard data in numbers like Supra but I can tell you if it helps a lot or a little lol.