To me, focusing through the view finder is far more natural than holding the camera at arms length, which compromises camera stability. Still, it's quite difficult to focus with long lenses due to narrow angle of view, but much better than without EVF. Is it worth buying the Sony EVF for the 5N? I would say yes, though I think the price is pretty steep for an EVF.
Blue flowers -- NEX-5N & Minolta RF Rokkor-X 250mm f5.6. Click for larger.
The requisite cat picture -- NEX-5N & Meyer-Optik Primotar 180mm f3.5. Click for larger.
Highlight -- NEX-5N & Minolta RF Rokkor-X 250mm f5.6. Click for larger.
Couple -- NEX-5N & Birns & Sawyer 150mm f3 Cine Lens