Largest wheel size??

I'm trying to decide on a set of wheels and I cant decide what size I want. I have a 2011 TRD Sport MG DC and wanted a larger set of BLACK wheels. I am choosing between an 18 inch and 20 inch. I know the wheels seem large to the off-roaders of TW but since its a prerunner im trying to run a "street fighter" look until i get out of college and can afford a 4x4 tacoma (hopefully there will be diesel by then )
Can ya'll please lend me your opinion and maybe post pics if your Tacos have either size wheel?

Thanks,
David

 

http://www.tacomaworld.com/forum/wheels-tires/78869-pics-your-18-s-20-s-33s.html