I have 40-622 (a.k.a. 28x1.5") tires, and Schwalbe offers two different sizes of tubes - their models "17" and "19" - as applicable for that tire size.
Ok, either one would surely fit well. But apart from weight difference (150 vs. 220 grams), is there any reason to prefer one over another? Is it better to have as small & light tube as possible? Or perhaps a bit larger and heavier one would be more durable, as it wouldn't be stretched as much? Err on which side?