Sleep after IM

Hello folks,
I am thinking of going into sleep (we have a good fellowship which just got accredited), but after speaking with the fellows one of whom is a psychiatrist and the other one an internist, who went through some hard time getting a job and ended up taking part-time and relocating to the areas that were not necessarily their first choice, I am now having some doubts. It looks like most of the sleep labs are owned by pulmonologists, who are looking for sleep-certified pulmonologists to join and share ICU call.
It would be great to hear from IM people who went into sleep or considering to go into sleep like myself.