I can see why you are not interested in Work Release!! ...no credits at all.
Have you considered Home Detention (Electronic Monitoring), is that even an option?
You have done your research very well... as for jail time the only solid answer can be the 1/2 time credit for good time / work time.
The rest of the possibilities that you mention are out there but you are at the mercy of whatever happens to be going on at the jail at the time that you are in custody. Even if someone knows what has been happening at your exact jail, no one will be able to guarantee anything for you other than they will get you out as fast as legally possible to make room for the next person.
If you get 120 days you will do 60 actual per PC 4019 minus any credit for time served. In addition, the sheriff can release you earlier in his discretion. Home confinement (SCRAM) is not an option for you in San Diego on a third DUI. You should inquire about work furlough, which is different from work release. Talk to your attorney about this option. It allows you to go to work and return to the work furlough center at night. You get the same credit as actual custody.
Most of my clients prefer jail over work release because it is much less time consuming. You will serve 60 days at most, but may be released much sooner. It is not that likely you will get out after serving 10% because this is your third DUI. It all depends on who else is serving time. Less serious offenders will get the early release before you do, but you may still be released much earlier than 60 days.
This answer is based on California law and procedure and does not create and attorney-client relationship.
60-80 days actually served in jail, depending on the date of your offense (before 10/01/11? from 01/25/10-09/27/10?). This is something you should have already discussed with your attorney prior to plea and sentence!
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