So for Constellations, getting a good feel for the models is as simple as reading the Gospel according to Desmond at the constellation collector blog, Polerouters have their own site, but where is the best resource to read about the calibres, cases, and dial variants used in the Calatrava?
Try PuristS Patek discussion group. Needless to say, they are very knowledgeable. Just don't expect the overwhelming response you get with almost any Omega group. That is unless you have a few 6 figure Pateks ;-)
John Goldberger published a very detailed book on the PP stainless steel watches. Costs about the same as AJTT.
I have seen the message only now By calatrava do you mean the "96 like" (which is "my" meaning) or all three hands Patek (which is then a ton of references, impossible to get all of o them) By 96 like I think of that case shape and a flat bezel with no step ( if you had a step or a non flat bezel, you can add 10 references or more...) Not 100% sure about calibers and diameters, if someone see a correction to make please share. 96 in 30.5mm, multiple calibers and dials possible snap on caseback 570 in 36mm , multiple calibers and dials possible snap on caseback 2457 30.5mm 27SC caliber snap on caseback 2545 31.5mm with the 12-400 2555 31.5mm with 27sc similar to 2457 but with screw down caseback. 3438 31.5mm with 27-460 caliber 3796 31mm 215 PS with the typical dial and dauphine hands 5196 37mm with 215 PS with the typical dial and dauphine hands There is also the small 438 in 28mm with 10-110 caliber .
I think the center seconds and automatics are more my preference, the 5127 is near perfect to me but I'm curious as to what came before that model and whether there are some interesting 5127 like predecessors that are still wearable size wise (IMO 34mm+)
In the idea of the 5127 there are only two references afaik , the 5107 with the flat bezel and the 5127 iwht the round bezel, I think thy are the same size. Then in 34mm plus and automatic all 12-600 and 27-460 should fit, the king being the marvellous 2526 imho. But other like 2551 are sublime watches. here is a list I made from auctions in french, I can copy it here if you like. http://montresmecaniques.forumactif.com/t3076-patek-a-mouvement-12-600-et-27-460 (2551 image has been lost somewhere bu you can find it easily )
Everything comes form Antiquorum except when credited Under: All have 12-600 or 27-460 automatic caliber. 2526 credit european Watch 2540 2551 2552 credit Robert Maron 2583 credit EHH 2584 3403 not sure on that one 3415 La 3425 La 3429 crédit Robert Maron 3433 crédit Robert Maron 3438 3440 3444 on the left with a 2540 credit: christies 3454 3466 3473 3485 3525 a boitier coussin 3542 3561 credit Christies with date 3445 credit: europeanwatch La 3514 credit: europeanwatch 3541 credit christies 3558 3565 Maybe there are others ; I just hope the references are the good one (Antiquorum is not always exact...)