No innacuracies in computing the profiles. Some computers are more sensitive and will beep annoyingly to warn you of excessive ascent speed. If the computer has download capabilities you’ll see them as little red lines in the graph of your dive.
I prefer a wrist mounted computer/gauge. the only thing I have on the hose is the pressure gauge clipped on the left D-ring on the harness. I find this is a much more streamlined setup and it’s the one preferred by most tech divers.