BOND, James Bond ---> MORE<---
As Paul said get a NICE vintage Sub not those 3 crappy ones LMAO Kidding of course although I'd prefer the early vintage Subs gilt dials the best. I think any of the non Big Crown Subs would be the one to get for stand alone Rolex or as a part of a true collection.
Just a note those some collectively call ALL Submariners without crown guards" Bond Subs (besides the venerable 6538 &6200 including the 5508, 5510, 6204, 6205, and 6536 series) although many purist would tell you there as there is only ONE true Bond - Sean Connery & his 6538 (with the possible exception of the 6200, on account of the presence of the larger Brevet winding crown and non-crown guard case).