has anyone used Krylon Premium Metallic Spray Paint for metallic finish on WWII bombers / aircraft? I am kind-of new to the metallic finishing idea so any advise would be helpful.

I have not. But, as I am still fairly novice to this, I can tell you what I know: Use Alclad II. I order mine through spruebrothers. It creates a gorgeous metal finish, and is easier to work with then a rattle can. Just make sure you get their gloss black primer as well. Just google search Alclad II, and the findings will amaze you!

I used the chrome silver on a pinewood derby car. The finish was smooth and brilliant. I've thought about using it on a model kit. It had a very fine spray pattern. On the wood surface, it needed a gloss coat to protect it as it smudged easily.

I don't have an airbrush. i also don't plan on getting one because i don't have the space for one.

They seem to do Alclad II metallics in spray cans nowadays as well.

Alclad II only makes one spray Chrome for lexan. I need aluminum. would i be able to use testors metalizer spray cans?

Metalizer in the rattle can would be the way to go in your situation. BUT, be aware that all the downsides to Metalizer still exsist. The surface must be absolutly blemish free. Any kind of mark will show up like a zit on Ann Hathaway's face. Any kind of chemical on the plastic and the paint will not adhere. Once dry, if you touch it, you will leave a finger print and it will come off if handled with more that kid gloves (cotton actually) There is a sealer made especially for Metalizer, and it works very well in sealing and protecting the finish. BUT, it also makes the sprayed on metal look flat and lifeless. More like silver paint and there goes all that work down the drain. Last, of course, is the fact that even low tack tape will lift the metal right off the plastic.
Honestly, your best bet is to go get Testors basic airbrush (about $20.00) and a can of Badger compressed air (about $9.00) and go with SNJ paint by Hawkeye (no primer needed, like Metalizer) which has the advantage that their Talon line is Acrylic based. No messy clean up. Or go with Alclad II, but they must have their own primer, black gloss for darker metals and white gloss for the lighter colours.
As for space, I just go outside and spread some plastic over the picnic table.

Have fun