I just went through all of this.
Superior was my first choice. Then, I decided I wanted a kit engine and build it myself.
I sat at the Matituck tent for 5 hours and watched an 0-360 grow before my eyes. After all of the details that make a good engine great, I decided against a self built kit engine.
ECI: If you use their injection, you need a return line. I didn't plumb a return line. ECI does not offer roller tappets.
Superior: Roller tappets and recent cylinder problems.
Lycoming: I believed them to be expensive.
Superior VS Lycoming roller tappets: Superior uses a standard case with a round hole for the lifter. The lifter has a slot in it. The case is drilled and a set screw is tapped to ride in the lifter slot to prevent the lifter from rotating.
Lycoming lifter for roller tappets has one flat side with the hole in the case machined accordingly to prevent rotation. Mattituck said they would build me whatever I wanted, but their choice in roller tappet engines was the Lycoming version: less penetrations in the case, simpler design.
Lycoming price: Van's has a special till the end of the month. I broke down and went with a Experimental lycoming from Van's. XIO-360-M1B, $23,950 with free shipping and long term engine preservation (pickle). All in all, with shipping, about $1K off from the final delivered cost.
The superior I wanted was going to cost ~24.6 plus shipping.
I actuall bought my prop from Van's back in Jan. If I had waited and ordered it with the engine, I would have saved an additional $1K off the price. And before you ask, I already did, the will not make exceptions. The prop/engine must be ordered at the exact same time to get the additional $1K discount.
I will have to pull the right mag and replace it with a Plasma-3. I can sell the mag on ebay and recover some of the cost.
And another thing I learned: The crank sensor for the Plasma EI bolts to the front of the case, behind the flywheel. These two bolt holes are for something that is no longer used. New Lycoming cases do not have these bolt holes. Mattituck said they would drill and tap if required. I guess I will have to go with the HAL effect pickup.
http://www.vansaircraft.com/images/open/Lyc-snf.jpg