This is a personal opinion, so take it for what it cost you - nothing. A quality O/U is a real joy and has some certain advantages, such as two barrels with different chokes and even two different loads if you want. A quality O/U handles extremely well and is very reliable. Good quality O/U’s retain their value and last forever with little maintenance. If/when maintenance is required it is easily done by qualified gunsmiths with top quality parts.
A cheaply built O/U is an abomination. They are bulky, heavy, handle poorly, and usually have poor fitting and inferior interior parts that eventually will cause a problem. If faced with a strict limit of $600 and I absolutely needed a gun right now with no time to save a bit longer I would gladly pass the cheap O/U and go for a good quality repeating shotgun like a good pump gun or semi-auto. It would be a smarter investment of money and one more likely to be trouble free over the long haul with the potential to hold a decent resale value. Otherwise, save just a little extra and buy a good quality used O/U. A Browning, SKB, or Beretta O/U can be had in solid used condition for around $1,000 - $1,250 and will put you miles ahead. In fact, you can find a good used SKB for probably around $750 and that is an excellent value.
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