After exploding another bearing ring in my BB due to sand infiltration - I like riding on the beach when there's a beach around to ride on. I'm wondering if I should switch to a sealed bearing unit. How much more reliable are they? Is the added cost worth it? $1.50 canadian for a replacement bearing ring is cheap and they're a piece of cake to install but dang do ya ever look silly walking your wheels off the beach with a seized crank. Any input would be appreciated!