I think the award for 'Most uninformed post of 2004 so far' goes to Toole
Price difference on the Eclipse & Halfblock comes down to one thing in my opinion, level of profit.
Halfblock is a nice marker, and at £875 competes with most mid to high end markers out there at the moment. This means that you will probably see a greater level of Race halfies being used over this year.
On the other hand the Nexus, retailing at £1275 is offering the bling factor to people. You aren't going to see a person on every team with one, cause there expensive, and therefore hold a greater level of exclusivity
Performance wise to the average person who picks up a marker and shoots it there isn't much difference. There both light, they both have electronic frames, although the frames do feel worlds apart.
To the technical people out there you can probably talk about open and close times and max this that and the other, but the average baller can't shoot 20bps so the fact they are capable of that is a moot point to me
If there is a big performance difference between the two though I can't see the addition of QEVs' making up that big a difference.
Like others have said try a race, try an e-blade, this will decide which marker to go for
Personally I like both of them, but like I said they do feel completely different