Well, if you think it looks better, it should be pretty much decided....
Okay, I'll impart the knowledge I gained working in a P'ball store.
Spyder: Pretty good value for money. User friendly, doesn't break down often. Lots of upgrades available, such as aftermarket barrels and internals. Well made.
Piranha: Pretty good value for money. As user friendly as they come. This marker is totally strip-downable in a matter of seconds! Whatever part you should want to replace, you can be up and gunning again within five minutes. Lots of upgrades available as well (same barrel threading by the way).
Piranha's edge over the spyder: User friendliness. Easiest to maintain marker in that price range. (plus looks, but that is ofcourse a matter of opinion)
Spyder's edge over the Piranha: Durability. I would say the Spyder is just a little less susceptible to wear and tear.
All in all it's a close race. It's really up to what you like best. Because of the only very small differences in durabilty, quality wise they are on equal par. If I had to choose a marker from that catagory, I'd go for the Piranha, because of it's ease of use, which is important to me.
You're bound to get loads of opinions though, my advice is try them out before buying. All that we have to say is just opinions. Form your own before chosing, based on experience, not on what a bunch of goofballs on a bulletin board have to say.
P.S. Please people, don't start shouting things like 'Get a Tippman, or an Inferno', it's hard enough for newbies to choose as it is, don't go f*cking this guy's head up with even more choices. Just be happy that he has been able to narrow it down already. And yeah, I know there are plenty of other good markers out there.
Peace.