Does this Airbnb seem to be a good stay for visiting San Diego for the first time?

Just to hijack the thread for a minute, wanted to mention that you should be prepared. People say the traffic in LA is bad, and it can be, but in SD it's worse. The land is hilly and there are only so many freeways that can be built, and there are a lot of cars. I'm always sadly amazed at how unpleasant it can be.

I'd also recommend you check out a vlogger named Steve with Sidetrack Adventures, he's based in SD and has been everywhere there.

I haven't lived in nSan Diego for some years, but both my children lived in the SD area for several years after I did, and I am sure the traffic has increased. From Spring Valley, with a car, you should have no trouble going to all the main sights. In my day (prehistoric times) it would be no more than a half-hour to Balboa Park (with its great zoo, etc.) or downtown. Maybe 10-15 minutes more to Seaworld/Mission Beach/Pacific Beach. It might be much longer during rush hour today. I would stay there.

I hope you have plenty of days in SD. Balboa Park alone has tons of museums, gardens, sights. And a day spent at Mission Beach (with what remains of the old amusement park , and the nice wide beach) is great also. I hope you are there during the Shakespeare Festival when the replica Old Globe Theater in Balboa Park is putting on a production. The zoo needs a whole day. If you are there on a weekend or holiday the carousel is fun to ride. Old Town SD is where the city began and it has some really good Mexican restaurants, plus historic buildings. And the mission in San Diego was the first one established in Calif. The nearby Presidio is on a hill with good views and is a nice place to picnic.

LA Jolla Shores is another good swimming beach. You could also make a day trip to Mt. Palomar to see the observatory, or a long day trip to the Zoo's Wild Animal Park near Escondido. Even Legoland is doable for a day trip (not my cup of tea).

Have fun!

It's not the worst suburb. I've visited there for a house party years ago. It was a weekend, so not much traffic and from our hotel near Embarcadero it was less than 25-30 min. It's not far from downtown, but I suppose during rush hour in the morning it will take you up to 45 min to downtown.

However my preference would be to be walking distance from the Gas Lamp quarter and the downtown. I also like Old Town, very quaint, it's close to downtown although you have to drive there.

Reading phred, I will have to agree that probably the traffic there is much worse than I said. However, the distances aren't long, so if you are saving a considerable amount on lodging, I would still stay in Spring Valley and just reconcile myself to a tiresome drive into the main sightseeing areas. Plan on being gone for the whole day and go home before ar after rush hour to limit aggravation.

I've lived in San Diego twice. It does have traffic, but I don't think it is as bad as LA. (I've lived there, too.) I do think Spring Valley is a little far out for visiting though. Have you looked in the Hillcrest/Mission Hills area or Bay Park which is just above Mission Bay Park. It would be perfect to be in one of the beach cities, but I'm sure that might be out of your budget. Be sure to do an entire day at the wonderful zoo. I love La Jolla for shopping, eating and walking along the beach. A favorite restaurant there is Brockton Villa which is above the cove and has wonderful views. I like taking the ferry from San Diego over to Coronado or one of the cruises in the bay. January is usually a great time to be there. Oddly May and June which are nice most other places are foggy and cloudy because of the marine layer of the ocean during those months. I usually visit in February or March each year. Yes, commuting is a pain as it is everywhere, just try to avoid rush hour in morning and afternoon.

I visit relatives in SD every year. Traffic can be bad during rush hour. Spring Valley is too far east to drive back and forth each day to see the sites you have listed. Consider Mission Valley, Ocean Beach, Mission Bay, Pacific Beach.
Even Clairmont, Kearney Mesa, La Jolla, Coronado would be better than Spring Valley.

so, to answer your question: Yes it would be pain to commute the main locations.