between this two, the 243 will be my pick. You can enjoy its 1950 Panerai well-known case and tritium indexes. If you love the 24, try to get the A, B, or C series as they all have polished bezels which make them look more special and fantastic.
I also support all Nicolas' point of views...the 64 La Bomba is my ultimate sub Panerai's ever made.
Unfortunately I can't find the 64, so I settle down with this one instead...
The 87..."Blue Bomba"...
Cheers