Great job, Kuting! However, and I know I'm going to sound overly critical about this (it's the writer in me I guess) I do have a few comments, bear with me:
-Backgrounds. San Diego's desert flats have numerous cacti, stray grass and tumbleweeds strewn about. That would help convey where they are. In addition, the spread showed Bobby and John's garbage, but they're too far from one another, and should have had a couple of backpacks just to convey they went prepared.
-Consistency. Page 2 panel 1 . John lowers hand with binoculars while Bobby throws away beer can. Panel 2 sees John with beer can while Bobby holds the binoculars (and the way he's holding it appears as if he held it for awhile) . Inconsistent. Better if both had Binoculars hanging by their neck.
-Props. John should have been holding the bat by page 3 panel 2, to suggest emergency or just about to raise it in the spread. As for the bat itself, a little tinkering just so we know it's a wooden/aluminum bat. See, if it's a wooden bat, no sheen; if it's a metal bat, the handle wouldn't have that strap .
-Design- Of the Alien stuff: gun...a little too familiar, not alien enough (looks similar to Cable's sidearm). Ship should have been above them...(it looks as if it's just next to Bobby...making it appear small), lighting them up(cliche, but it presents immediacy) to emphasize the boys are going nowhere but with those alien sodomists. I noticed you used Elvish runes on the ship; good idea, but you should take care not to overuse them or give it your own spin (so you won't be accused of ripping off anybody...you know how it is with these fanboys). Maybe added some swirls effects on the symbols or further divided them into parts would make them more exotic looking (and why does it spell your name?) As for the Aliens themselves, Pointy ears are passe (Vulcans, Elves) unless you put a little spin on them. Extending them a little furter up would make them look more sinister
-Emotion. Slightly lacking, particularly in page 3 and the spread. John and Bobby's demeanor and posture should be more nervous and confused by page 4-5.
-Overall - I know, I sound as if I'm nit-picking. And what do I know, I'm not an artist. I'm a writer. But I really found it very good. Much better than my "artwork". As I've always told you, you have the talent and the passion to make it big in this crazy business...this is proof of that faith in you.
P5,000 is just right for all the work you put in this, Kuting. I told you it's acceptable for such quality.
See you soon, Kuting!