Honestly, neither. I have tanks with both of those and neither work that great and require trouble shooting everytime we visit.
The Coralife pump is very very strange and doesn't work right 50% of the time. We've found that butting it up to a sump wall and offering the intake some resistance helps but it still has a very real chance of overflowing. Gabriel (GKarshens) used one for awhile and I hope he chimes in on the difference between it and his Euroreef.
The Precision Marine skimmer is just an outdated technology IMHO. Mag 9.5's are not good with head loss and back pressure, they produce tons of heat, and the amount of air it's able to draw just isn't very good. We have a larger model with an Iwaki 50 driving it and it's never done anything for me.
Look into Euroreef as they make some really fair priced needlewheel skimmers. You're paying for reliability, performance, the ability to set it and forget it, and lower power consumption and heat. A RS-80 made out of extruded acrylic is only $178.99 on Marine Depot. http://www.marinedepot.com/aquarium_protei..._rs.asp?CartId=
John