Lovely watch even if I would prefer the white gold version. Mine is ref 386-88 with display back. Others have a solid case back in relief. Some versions have a pulsometre scale, others like mine a tachymeter.
I like the manual wind, stepped bezel and overall look of the watch. I agree with the other comment that they are likely more scarce...the 5070P especially so. My preference shows in this photo from my collection. Dave