How do these binoculars compare to Helios or Opticron - does anyone know?

Tech Specs:

Shell Material:

alloy 

Magnification:

8 X, 10 X 

Objective Lens:

[8x] 394 feet at 1000 yards; [10x] 315 feet at 1000 yards 

Exit Pupil:

[8x] 4 mm; [10x] 3.2 mm 

Waterproof:

yes, weather-resistant 

Eye Relief:

[8x] 16 mm; [10x] 15 mm 

Minimum Focus:

4 ft 

Weight:

25 oz 

Recommended Use:

bird watching, sports 

Manufacturer Warranty:

lifetime