Iphone: Doom Resurection

I have been tempted to pick up this game. It is an on-rails shooter but you use the accelerometer to move your aiming reticule. You have a dodge button but move out of the way of projectile weapons and of course a shoot and reload button. The graphics look pretty good but $9.99 is a hard sell on the Iphone. It has 4 difficulty levels and a grading system so there is some replay value. I will wait since they had a sale on the Wolfenstein game within a month of release.