As much I like the Pipe Meter, I would be more useful to have a flow meter which would tell how much fluid traveled out of the pipe per tick instead of the current fluid level. With a flow meter and a combinator, it would easy to calculate how much fluid has passed through or how much fluid is within a pipe system.

Flow can be calculated from level differences. Plans for that used to be on the forum.

Implementing the same in lua script would have worse performance than a small combinator contraption.