I second carbon adaptors. Make sure to get one with a built in screen IMO. Got mine from apix design and super happy. Probably will pay for itself with the amount of isopropyl alcohol I'm saving.
Definitely adds drag with the type of carbon I'm using (had it laying around) but I'm going to try larger granules of carbon. I just pull the adaptor with my slide though and no drag when clearing which is when it counts. I actually prefer the drag when milking.
I have the Roor one and enjoy it very much. Be sure to buy a glass gauze for it as well. What I like about the Roor is it is super clean work and pretty short compared to McFinn's and others. Use rinsed activated charcoal and fill half full at most. Too much carbon gets sticky and increases drag big time.
Deff get one with a built in screen, anything with drop in screens will drag real bad. I also use petco pellets for my filter, still does a good job (prob not as good as smaller granules) filtering the smoke, and has alooot less drag then fine carbon.
