Complex and not necessarily effective

Blah blah. The value of this counter? The altimeter. I am writing after 1 year and a half of use. I affirm that this function is ineffective. I live in Lyon, I leave home, I'm one meter below the sea level! I think that in fact the extent of the altimeter depends on the proper trimming of the starting altitude and is conditioned by atmospheric pressure. What makes the same journey in the summer and winter will not give the same elevation gain.
In short .... It remains the basic functions, distance, exit time, max speed. On this point the meter does the job; but it's the least we expect from a counter at this price.
Especially since it is complex to change winter time in summer, to get out the manual.