Well, I removed the VTCS valves on my 2.3 Mazda3.
What a mistake!!!!!
In any temperatures near or below freezing, the car is almost undrivable until the car is up to near full operating temp. The car bucks, and sputters until it hits about 4000 RPM, then it just takes off. Driving in snow out of the driveway is almost impossible. Either the car just sputters and falls on it's face, or it just goes WOT and spins the wheels. After it fully warms up it is normal, but it is just not worth it. The benefit is barely noticable.
Also, my fuel economy has gone into the crapper. My last tank went down to 350km before the light came on, where before I would get around 450km before the light came on.
I will be putting the valves back in as soon as possible.........