engine modifications

[Bewildered@aol.com]

I'm new to this list and I've searched the archives but haven't found much on
this subject. I have a '94 S4 and want to use either the Ned Ritchie chip and
manifold or the Joe Hoppen chip and manifold. I'm not sure which I should go
with and would appreciate any feedback from anyone who has done these mods.
How do they compare in performance? And what about reliability? I don't want
to destroy the engine at the expense of more power. I've heard of blown head
gaskets.
Any info will be appreciated greatly.

Bill