mate, you'll get a million and one responses on this though most of it has already been said, asked, replied before, I'd have a search through the threads before going much further. I can only speak from my own experience which amounts to a y and z boarded egg at the moment though I have just received a reloader-b , can't comment on that yet though as I haven't used it on a marker.
A general rule of thumb from what I've seen here seems to be:
On a budget - egg2, y or z-board
Average Joe - halo, reloader, vlocity
Moneybags - pulse with full rf setup
Withe the reloader, halo, vlocity it seems to be down to personal preference though as the halo is optical it can have issues with certain shell types. they all seem to cost about the same and feed at similar rates....