Surgee

Some quick questions for my first time in DXB airport coming up! I have an early morning (8am) short haul J departure (under 2 hours) after 1.5 days work in Dubai and thinking about upgrading to the F lounge over J for $105 USD for the experience. I will be jet lagged so showing up at 3am to "maximize" the experience is fine, and my hotel is nothing fancy. Questions:

1) Overall worth it to try it out for 4 hours?

2) If I'm a lounge "upgrade" pax, am I still eligible for shoeshine and complementary spa treatment? I will be in need of a shoeshine anyway, and in DXB thats already going to set me back! 2a) Will those services be available at 4am?

3) Anything else not to miss if I do it? Breakfast salmon look tasty.

edit to add: 4) Is 4 hours billed as from your departure time, from your boarding time, or from the time you walk in the door? That is, when should I show up?

Thanks!
-Surgee