First off thanks to everyone that has served. It's definitely not an easy life serving in the armed forces.
Jeff, I think as long as you know exactly what you want to get out of joining the service, you should be fine.
My uncle served for 32 years in the air force. Joined up when he was 18 and flew phantoms in 'Nam. Ever since I was old enough to speak he would bring me model jets, toy jets, etc. I guess you could say he was "grooming" me to follow what he did. After high school I went a different route. Had I known what I know now, I would have followed in his footsteps.
One of his sons, my cousin, joined up with the army, went into Ranger School, spent several years as a Ranger, and now I'm not sure what he does, I know he's still serving though. Haven't spoken to him in a few years.
The pay is meh, the benefits, if utilized, are fairly good. My only advice is to make 1000% sure you are going to want to serve for the next 4 years. It's not a job you can quit because you don't like it. Seeing how dedicated you've been to reef keeping, I don't think that will be a problem! Just something to consider.
I wish you luck Jeff. Let me know if you need anything.