I am a big fan of round shift knobs, and have gone through about 4 of them trying to find one that I really like.
The Whalen Shift Machine that I had left over from my Mini is almost perfect, but being solid stainless steel it can get a little uncomfortable if it is too hot or too cold out.
I have also tried the CravenSpeed, and the Black Forest Industries knobs, but they were a bit too big around for my taste - and also pretty expensive.
I found a couple of cheap delrin knobs on eBay (about $15) and figured I'd see if I could make them fit. It turns out, they fit really well. I tried both a 50mm and a 44mm version. I think I like the 44mm better for the way it feels it the hand.
https://www.ebay.com/itm/New-50mm-Bl...5/182929322008
https://www.ebay.com/itm/New-44mm-Bl...5/113293600642
Both of them came with M12 threading, and our shift levers are just a little bigger than 14mm, so I had to progressively ream out the holes in the knobs with 12mm, 13mm, and 14mm drill bits. I don't have a drill press, and I didn't want to risk putting a hole in my hand, so I just chucked the bits in the drill, then twisted the knob onto the bit by hand. It turned out to be really easy and quick. The fit is perfect too - it is really tight, and presses on by hand. The knobs won't rotate or pull off without a lot of force, so there is no issue driving.
I also cut a bit of aluminum tubing to fit over the shift lever, because it just looked a little weird being so skinny. I can still take about another 2mm off of the one shown in the picture below, so it will be a little shorter when I'm done.
Overall, I really like it. I don't care for the stock shift knobs at all, and I had been using the BMW Performance shift knob (kind of straight looking with alcantara) and like it, but prefer the round knob - it is just much more comfortable in the hand. The material is great, and doesn't hold heat or get too cold to touch. The only thing I would have liked is a little more weight, but it really isn't a big deal. I would also prefer to have a shift pattern, but only for aesthetics.
I know, nothing ground shattering here, but I figured I'd share anyway...
