Calculate Resource Availability

Which one do people usually use for this setting? Default Calendar or the Users Schedule? I want it to take into consideration time out of the office if they put it on the calendar and I also want it to take into consideration they are only worth .75FTE. I read that if you use user schedule it ignores the FTE calc. However, if I use Default schedule, it doesnt seem to be moving the project tasks out if over capacity or out of office. IS thee another setting?