The Omega requires much less strength to operate, clean-up is much quicker and won’t jam up like the Greenstar. Juice quality is probably better with the Greenstar. It really depends on what’s more important to you. I personally cannot phantom myself fiddling with the Greenstar on a daily basis; others would disagree.
If I can only get one juicer, I’ll get the Omega 8006. It’s a user-friendly, versatile, low-risk machine to get started. If I can get two juicers, I’ll get the Omega 8006 and the Breville Citrus Press or any juice press. When you’re on IP, you’re doing citrus left and right. A citrus press really comes in handy.