Hey Pakriff,
There is a fairly large group of generous, voluble, and remarkably knowledgable Martin enthusiasts on SotW--an honest to goodness great bunch actually. My guess is that they haven't responded to your post because, in fact, the issue of key heights on Martins has been discussed quite extensively in the Martin forum, and they would like you to search there before asking your question.
I'm not an expert, but if the keys are set relatively low, that sounds like your horn has been set up properly. If they're too low, your sax will play flat and the intonation/tone quality will be inconsistant across the range of the horn.
Sounds like a wonderful sax. Congratulations.
Rory
ps. what mouthpiece(s) are you going to use on it?