Wow, you both have lost me. Rendezvous, these guys like to make their own stuff. If you don't have anything positive to say, please don't belittle their efforts (intended or not, that is what you're doing).
My own input on this, is that servo motors (particularly the good expensive ones found in large scale servos), are expensive because they provide high torque from low power. My only worry is how much current a wiper motor will pull. Got any info on that?
PS. A LOOOOOONG time ago, I used to manufacture (just another individual on the production line, I used to install the stators) and test the wiper motors that clean the headlights on the challenger II tank!! We even use to test the coverage arc by spraying an analog 'headlight' with baby powder, then wiping it off with the wiper blade attached to the motor! CAn you imagine all those Royal Marine engineers opening the boxes and going 'Why the HELL do these things always smell of baby powder!!?!!?
I also used to test the engine cooling fans (1m hydraulic fan) for dangerous blade imperfections (spinning them overspeed on a hydraulic rig. Even in a sound proof room, the howling could be heard kilometres away!!! :O)