regardless what you choose, you will never see any real power benefits, its all down to personal preference regarding the noise and OEM look, if you want the OEM look stick with the airbox and add an uprated panel filter such as Pipercross, K&N or ITG.
If you want the pschhhh louder then go for the ebay toyosports induction kit setup, the filter goes behind the front bumper though and is too close to the floor for some peoples liking so some chop around 1-2" off the end of the tube.
And yes your sensor (MAF) is directly after the airbox inbetween the TIP and airbox