Is there a big enough difference between the two to pay the extra money? Should we even consider the 4 gear billet servo also?

 

If you want a hard shift go billet, softer go vette. it also depends on if you have a shift kit and how its tuned
billet with shift kit and upped pressures equals backbreaking shifts

 

billet servo is aftermarket, corvette is the bigger stocker one that is OEM.

Not sure of pressure differences but wouldnt expect much. of the corvetter vs billet

 

I'd go Corvette servo for 1-2 and a Billet servo for 3-4. Nice firm shifts that'll help it last longer but not so hard that you break stuff.

 

Personaly, I went with the billet servos from trasmisioncenter.com Im glad I didnt go any other way. Before my nelson tune I got quick and firm shifts, very impressive considering the servos being the only mod on the tranny. After the nelson, I FELL IN LOVE!!! It shifts as hard as I want it to. Just crusin around the shifts are noticeable but not neck-breaking by no means, but when I let her breath a lil, then she can break the 20's loose going into 2nd . I would highly recomend goin with the billet servos and a healthy tune.

 

With corvette 1-2 servo, slightly higher than normal shift pressure, and 280rwhp I was able to leave a 2ft blackmark on fresh blacktop during a WOT shift at 50mph. Normal driving it would chirp. which was cool, but isn't necessarily a good thing on the internals or rearend.
Dropped the pressure back down to normal and now it's a nice firm 1-2 under normal driving and WOT will flex the front suspension (thanks to the great tires).
It's really going to be your opinion on what you want. I've seen guys go full billet and bring up the pressure and then take the thing back to the shop cuz they can't stand how hard it hits. You can always swap out servo's if you want, since it's easy, but I don't see any reason to get billet 1-2. With a vette servo you can bump up the pressure a touch if you want some more firmness and then when you mod out more later you can bring it back down.
BTMO