If you are a scuba diver, work full time in the diving industry, or at least spend all and each weekend down at the dive centre / dive site then IMHO maybe, just maybe you wont tire of that PAM within a year - max two.
Now against that, that IWC will continue to look good on your wrist, during the week, with or without a suit, on weekends with or without a diving center / site in sight, for ever and ever.
Need to finance it, by off loading another watch - so be it. It's not getting sufficient wrist time - against this beautiful INGE which looks great on your wrist!
And, that IWC has a great movement in it too!