Sunny 16 is not only reliable, it is GOSPEL!
That's what I use when using the SV or when testing older cameras.
I wrote this for a Photography Basics seminar I do.
Soleado = 1/ISO @ f16 (sunny)
Levemente nublado = 1/ISO @ f11 (slightly overcast)
Nublado = 1/ISO @ f8 (overcast)
Bien nublado = 1/ISO @ f5.6 (heavy overcast)
Sombra = 1/ISO @ f4 (shadow)
Keep in mind neg film is quite forgiving in latitude, meaning it can handle variations quite well. I was recently shooting a pre-set lens with ISO100 film. The lens was set at f16 and it was bright and sunny outside. It was opened to f2 for composing and I forgot to stop it down to f16 and took the shot. In digital, that would have been an all white frame. It came out only slightly overexposed but quite usable!
Thanks,