Bought a aimpoint pro a couple years back. I carried its big brother along with a acog in iraq and Afghanistan. Never had a issue and both sights were built for abuse. For civilian use i figured the pro would work without the heafty price tag that comes with a comp 4. After 2 years of abuse on a farm the pro has held its zero and has been perfectly reliable. Last month i picked up a colt 6920 and decided to try a sig romeo 7. The romeo 7 cost two hundred less than the pro but appeared to be well built. After mounting and a quick zero i put it in the safe, last week i caught a raccoon in the chicken coop so i grabbed the colt turned on the romeo 7 and ...no red dot. I changed the battery and still nothing. Called sig who sent me a fedex label. Might have got a lemon but even if they fix it i will always lack confidence in its reliability. Sometimes its better to spend the extra money on what you trust. This is not a knock on sig as i love their firearms and customer service is second to none