Omega 004 is described on the website as being comparable to Wyeast1056/WLP001, so your second pitch probably won't change your beer that much.
I'm kegging 5 gallons this weekend that used Omega DIPA (Conan). It was very fresh - I pitched it 3 weeks after the packaging date.
1 minute pure O2
1.5 L starter
Fermented at 68
It was pretty quiet for the first 18-24, but then took off like a rocket and achieved 78% AA. And I like what I'm tasting so far.
The package says use starter over 1.060, but I would make one regardless.
As others have said, Starter + Oxygen + Temperature = Tasty Beer