I fail to see how those legs are better than a set of wheels. If the legs has much more dynamic range of movement than this one, then I'd say it's better than wheels at this point.

The problem with this kind of legs, it's limited to one set of motion. Which isn't much better than wheels.

When designing a bot for a pipe, you could just plant the wheels on the side with a bit of force to avoid the junk on the bottom completely.