Had the opportunity to pick up a CMI set up for a pretty sweet deal. Currently have manifolds wondering what difference if any that I'll notice switching to the CMI's.

built in water injection!

Thta would depend on what manifolds you have, what CMI's you got and how much power you are running. On a 500hp engine, I doubt you'll see a difference.

No doubt. With all the problems CMI has had with grenading engines due to their leaky tin cans, there's no way I would go out and buy a set to put on my boat! If I were buying a replacement set, I'd go with SM.

CMI... too many problems being reported.
What do you have now, Imco powerflow?
If you were to upgrade to anything w/ your 650+hp, it'd be to a Stainless Marine Gen III.

I believe they're Etops and I was able to get rid of an item worth about half the price of the CMI's I traded for. If they're not worth putting on, I'll sell them.

546ci 650hp(ish).

From the vid in your signature, it looks like you have Gils. You should gain a little bit with the E Tops and your HP. If I had to guess, I'd say maybe 20hp.

If I see CMI's on a boat, I look at them as a liability.

They look great and make some power, but they're pretty expensive and ticking time-bombs!

I've had Gil manifolds crack, but my CMI's have never had problems.