I have use many different cameras with built-in meters, eg lots of Canon EOS camera, Nikon F3/F5/F100/FM2n, OM1, Rollei 6000 series and the 2.8FX, etc etc. I also own a Sekonic 358 and owned a 308 and a 558.
Now...as much as I trust the Sekonics...I have never ever had a problem with built-in meters. All you do is you shoot a roll or two and you learn what the meter does. In fact, all I ever needed to do is have a think if the sun or some bright light is in the background. If there is, I recompose and meter without that bright source in the frame, exposure hold, recompose and shoot. Done. Then again, I don't find it that much of a hassle using the Sekonic if I have to, the light does not actually change that much and if shooting C41 who cares a stop either way. Lately I just use an app on my phone, it works for anything from daylight to reasonable indoor light levels.