solid advice from archibald.
the first step is probably deciding what type of pam you want. there are several main categories to consider:
i) base historic models such as 005, 111, 112, 127, 217, etc
ii) radiomir models such as 183, 210, 232, etc
iii) submersible models such as 243, 187, 092, 199, etc
iv) other models with more complications such as 212, 063, etc
fwiw, if i could do it all over again, i'd get the 112h as my first pam.
good luck with the decision
deltatahoe