I purchased several of these ranging from Macaw size down to Amazon size and I've been pretty happy with all so far. However I do want to point out that between the two orders the size of the ones I purchased for my macaw were drastically different. The first was perfect for her and was roughly 2.5' × 3' with two large forked branches. The second however was ok but I'll admit I was slightly disappointed compared to the first. The second one was MUCH smaller over all (2'×1') and looked like it should have been with the next size down instead of the largest size. I also had to hack off one branch because it twisted around parallel to the main beam and made a narrow openning that I was afraid my rowdy macaw would get herself caught in. The 3rd branch I ordered looked awesome but didn't give much room for perching due to the excessive twisting of branches... however we fixed that by turning it on end and bolting it to the TOP of our ekkie's cage and used it as a play top piece, which it works perfectly for. He LOVES climbing up and down it and perching on the top branch that happens to make a perfect perch now! When I get pictures I'll make sure to post them. Going to purchase another large for our newest BG'S cage, as she only came with the original dowels for it and they're creating rub marks on her pads now.
As for the smoothness, we haven't had much issues, but then again most branches are in the big mac cages so they customise them to the point that they're scared up enough to become "tacky" on their pads. The one branch that isn't belongs to the younger BG who likes to actually slide down the larger branch when she's playing. But to solve this problem in the medium sizes we've purchased rough toothed grinders for our dremal and used that to scar up the wood to create traction on smaller feet who don't have the beak strength to do it themselves. ^_^