Just noticed some of these have a top "cap" which sits over the stem vs flush with the adapter body. This means that if you want to remove the stem to swap out and try different ones, you still need to remove the entire stem and adapter for a stem swap. If you unscrew the top cap fully the wedge falls down into the fork and you have that mess to deal with.

The VO adapters are really nice. They are flush so you dont have this problem/annoyance and they are a bit longer if you want a bit more height. The Origin8 ones......not so much. THey work but they have this stupid top cap design which after you are all wrapped and cabled might make it really hard to get your stem+ adapter out without undoing your brake cables at the calipers to get enough slack to pull the whole assembly out. Not a huge deal but not quite as quick as you may want for a simple stem swap.

There are some generic stem adapters which have the flush cap too but i find that those are all steel and really heavy. My vote would be the VO adapters every time.

Not sure that anyone really cares The only real advantage that i can see from going from quill to threadless is the ability to try different stems and potentially bars to see what fits you best and swap out quickly without the mess of re-wrapping or messing with cables. YOu are not going to save any weight going this route.

Its sunday...its raining and im bored. I just observed this after sitting here staring at my bikes while drinking my coffee.

i have used the vo adapters several times and they work really well.

yup....they have the best finish too out of all the ones i have tried. They are a bit more expensive than your standard adapter but i think they are worth it.