The conclusion I've come to is twofold : 'there isn't one' and 'if there were, it would be called Fibracell'! After years of throwing out 1/4 of the reeds in a box, or sanding and trimming to save stuffy, poorly cut or worn out reeds, I gave up and tried Rico Plasticovers. They are definitely brighter, longer lasting and more free-blowing, but I found grading inconsistent and had trouble with 'chirping'. I tried Bari clear plastic reeds and found them durable, but tone was monochromatic and they were best outdoors or in a situation where tone wasn't as important, like marching band.
Finally, I found Fibracell. These are a resin/Mylar composite that look and feel very much like natural cane, but the resemblance ends there! They are durable, consistent, don't require soaking, don't get soggy, don't split, crack, warp or squeak and are more free-blowing (important for Jazz and Commercial players who want a brighter, more open sound) than cane. Each reed costs about $9, but will last for months. Many pros and teachers now use them, and I've had good feedback from students as well as improved tone and performance in my playing.
There are a couple of mitigating factors that need to be taken into consideration, however: 1) they run a little softer than cane reeds, anywhere from 1/2 to a full grade. So, your tenor sax 2.5 will become a 3, and your clarinet 3 may become a 4. And 2) I find the stiffness ratio of tip to heart is a little different than cane, so intonation and articulation will have to be adapted accordingly. Regular practicing over a period of a couple weeks should make for a good transition; I wouldn't take one out for the first time on a gig!
I know these are more popular with saxophonists than clarinetists, but I recommend them to anyone looking for a more consistent, free-blowing reed. Especially for doublers, they can't be beat! Buy a couple in different grades, try them for a couple weeks and see if you don't notice an improvement in your tone and intonation. Then, throw away all those half-full boxes of half playable reeds and don't look back.....