I’d start with the 5 amp then switch to the 2. When it was exhausted, I’d get the 5 to finish. Early this season I’d use the 5 twice, 2 twice, then finish a small area with the 5. By August it was the 5, then the 2 for a pass or two Then wait for the 5 to recharge. 5 length seemed normal. But the two was vastly different.