Nicolas,
Nice to see you joining the ranks of Speedy fans at last. Or maybe I should say owners - after all you've been a fan for a while I think but just not taken the plunge!
My dream would be the CK 2915 pictured on page 100 of Omega Sportswatches by John Goldberger - steel bezel, arrow hand, gorgeous lollipop seconds! I'd prefer it on a strap like the CK2998 on page 114 though!
So, based on that, if I had the opportunity I'd go for the oldest, most original (I hate replacement hands/bezels/crowns etc) Speedy I could afford and, if thats a CK2915 then you're blessed.
Every so often I take tha back off my modest 105.012 and gaze at the movement. It's a classic and a beauty to behold, and I love the richness of the various finishes - polished screws, copper, brass etc.
Enjoy your dilemma, then enjoy your choice.
With very best wishes.
Vernon.