Hi Simon. I use Various reeds across my horns; on soprano either Rico Royal 2.5 or Plasticover 3, on alto Alexander Superial 2.5, Rico Jazz Select 2H or Rico Royal 2.5, on tenor RJS 2M or 2H, or Rico Royal 2 or 2.5. As you can see, I'm quite flexible with reeds, but I like the Alexanders on my alto best, and would probably use them on soprano and tenor if I could get them locally.
Cheers, Bob