Missions are completely different. ELINT/SIGINT vs. ASW/ASUW/ISR/MIW/HADR/whatever the fuck else the Navy decides to saddle you with with no notice. EP-3 deals with some if the most high-priority mission sets in the entire military. P-8 if you're good enough you might get to blow some shit up. Most of the details can't be discussed here, so find an instructor and a SCIF.
P-8 squadrons deploy for roughly 7 months at a time first in/last out. About 11 months on home-cycle. The squadron is typically split between 2 locations, sometimes more. You'll see your friends a decent amount, and get to see some fun places, but almost always be with the CO/XO or senior DH. VQ-1 sends crews out on 3 month detachments. They go to mostly different places, usually with an O-4 in charge, sometimes with an O-3. Gone for less, but much more frequently. Usually much less notice when a bird needs to be swapped or a new requirement gets mandated.
As a pilot you'll have a good opportunity to reach mission command early if you work hard, but your job will really be to fly the aircraft to the op area. The real work gets done in the back of the plane. Some single anchors will disagree, but they are kidding themselves. I'd assume that pilots are more involved in the P-8 missions because flying ASW patterns requires coordination between flight and TACCO, but a EP-3 pilot could correct that.