I used to grow them up north in Oakland and they are great. Asian pears sold commercially are often picked before they are ripe - once picked, the fruits will not ripen further so homegrown are even sweeter.

While most Asian pears are partially self-fruitful, they'll produce more and larger fruits with cross pollination. If space is limited, choose a tree that
includes several grafted varieties on one trunk. Although it's a European pear, 'Bartlett' is a good pollinator.

There are many, many species, so choice depends on largely on getting a low-chill variety (Pasadena is just about the far end of acceptability, so warm winter years may produce fewer fruit). But flavor varies depending on climate summer warmth to sweeten flavor and the trees hate humid summer conditions, so Pasadena is great for those requirements.

Many growers agree that adding trace minerals, such as rock dust, to the soil results in better-tasting fruit, so the granite will help.

Drainage is very important. You can cheat a little on chill requirements by planting on the shady north side of your house or a low spot on the property where cold air settles. But water can gather in low spots, so don't sacrifice drainage for chill.

Because of the warm winters, these may be your best choice (need about 400 hours of temp below 45 degrees).
Chojuro- ripe mid-August
Hosui - Early Sept.
Niiataka - Late Sept.
Shinko - Late Sept.
Tsu Li - Late Sept.
Ya Li - Late Sept.

Fireblight is a major concern for most species, so try to keep leaves and fruit dry in summer/fall, make sure your plants aren't being infected by aphids, leaf hoppers, or beetles and prune ruthlessly if branches start to wither.

I have the cultivar 20th Century in my Berkeley garden which is borderline zone 9/10 conditions. I've found that in warmer winters there is little fruit set, in colder winters it does quite well. As it is located in the tight 8 foot wide space between me and my neighbor, winter lows are moderated by both houses radiating heat in winter. No other pear tree close by to cross-polinate, but it does generally bear well. Only occasional problems with fireblight in my location, and I would suspect even less so in warmer and drier Pasadena, it is the late spring rains during bloom season that spread it. My tree always seems late to bloom/leaf out, and I suspect this is due to lack of ideal hours of winter chilling.

We have one and had fruit from it last year.I don't even know why DH bought it,as neither of us is a pear lover.He hardly eats any fruit,and with pears i can take them or leave them,and i usually do the latter.
Kathi

PS,I'm in Oceanside,along the coast.