Feature:
The interior surface of the slide is rough and porous making for virtually no slippage on your finger.

Quality:
Dunlop quality. A.k.a. The Best quality.

Value:
You're paying for a "signature" product so of course its more expensive than others. If you can find the Dunlop Porcelain Moonshine slide, it's the same thing so I recommend that as a cheap alternative.

Desirability:
I found it very hard to find any porcelain slides out there, and I love their tone. That alone made this very desirable to me, but of course Mr. Perry is on bad mutha' and who doesn't love Aerosmith? Some people may not like the whole signature thing, but its tone was more than enough to win me over.

Sound:
On acoustics it resembles a glass slide, but with a bit more volume and midrange response. As for electrics its tone is slightly brighter than glass, not nearly as noisy as metal slides, and sounds big and bluesy like a slide should. No matter what you use it for, its tone is superbly soulful.

Ease of Use:
Big fingers beware! The large size won't fit comfortably over my ring finger knuckle, but i like it above the knuckle anyway. If you use your pinky, then this is totally irrelevant, so don't worry.

Overall:
If you can get over the signature stigma like I did, you will be very pleased this slide. From Delta blues to country licks, if you need a little more soul, this slide will get you there.