I just got to try cattley guavas for the first time, both red and yellow. They grew and fruited quickly from seed. I like them much better than any of the true guavas I've had so far (large crunchy white, pink, "regular" green/yellow). I like the yellow ones a little more than the red, slightly sour while red is all sweet.
This yellow one isn't fully ripe, forgot to take a picture of the ripe ones I ate.