Just to clarify, the Zip is a low compression ball (actually a zero compression core, hence the name Zip) which is what helps in reducing a slice. The spin comes from the softer cover. When I played them I had spin around the greens due to the soft cover and a lot less side spin off the driver due to the low compression core. My normal slices where more of a fade.
The e5+ is designed for spin but the e6+ is designed to fly longer and straighter.
The best thing is to do what I did this year, find the part of your swing that is causing the slice. Brian Manzella's site was a big help for me to the point I took the right side of the golf course out of play. My main fault was a cupped left wrist at impact which left my club face wide open.