If you can find seats in section 230 for under $20, pull the trigger. I spent $60 on two tickets in row 14 and definitely felt a little let down by our vantage point. It does, however, overlook the picnic area and you can see bits and pieces of the Padres bullpen from these seats. You CANNOT, however, see parts of the warning track if the ball actually reaches there (outfield is super deep at Petco Park).
You also will have to turn around to look at the jumbo screen displaying all of the game information since it sits above these seats. Wish it was bigger.
The bleacher seats are the worst seats in the building, they use the little beach area to fool you. Those seats have no cup holders or backs to the seats. So beware. Those tickets are cheap for a reason.