Calrose also makes a good rice pudding. It releases a lot of starch, making a creamy sauce. I've also used it to make risotto and I think it does a good job there also. I can't see a lot of difference, but true risottophiles probably would.
Here's a story in the NY Times about using American medium grain rice and sushi rice to make risotto, and the results.
An American Rice Stands In for Risotto - NY Times March 15, 1989
Here's a recipe from Australia that mentions you can use Calrose to make Seafood Paella:
I haven't used Calrose for risotto or paella style preparations. One thing the puzzles me is the differences in water to rice ratios.
Calrose instructions usually specify 1 1/2c of water per cup of rice (after rinsing). This is lower than the 2c usually specified for long grain. But sources describing some of the Italian and Spanish short/medium grain rice extol their ability to absorb liquid, some claiming a 3:1 liquid to rice ratio. But risotto and paella are cooked without a lid.
describes various rice types (with calaspara and calrose together to compare).
Calrose is most commonly used for Asian, especially Japanese, cooking. I'm surprised that this source says it works well for paella. But I'll admit that there isn't a lot of difference in appearance between arborio and calrose rise grains.
I think most of us rely on authorities rather than our own experience when it comes to choosing rice for paella.