If we accept the fact that Patek Philippe, Audemars Piguet, and Vacheron Constantin are considered to be the "Holy Trinity" of high horology. And it is a known fact that Jaeger-LeCoultre supplies movements to each of the brands in the Holy Trinity. The logic begs the question: if JLC is the watchmaker to the Holy Trinity, why isn't JLC a part of the Holy Trinity?
Although... If you look at AP, some of their models have pretty basic finish. And if you look at Vacheron Constantin, some of their models use a base caliber that isn't well finished (like the FIFTY SIX and some ladies watches). And some of the JLCs do have good finish!
Dive watch, get something cheap. Or use your AP. Honestly, the best dive watch is the Blancpain 50 Fathoms. Beautiful movement finishing. Not cheap enough though. A Longines Legends Diver would be another great piece! That's reasonably priced.