I've had a 1200 since the mid 1980s. Mom and Dad bought it for me at a garage sale. It's a 12 gauge with the Winchokes.
I've had it apart for some time refinishing the stock. I really need to complete that. The varnish was pretty scarred up from years of use.
The 1200 was a radical departure for Winchester in that the traditional shotgun bolt lockup was abandoned in favor of a rotating bolt head that locks into grooves in the barrel extension.
This makes the 1200 one of the strongest shotguns ever fielded by any maker.
I've fired probably 15,000 rounds through mine in the years that I've had it, and it never failed to feed, fire, or eject (except with cheap assed Hungarian bargain basement shells).
It's biggest drawback is that, compared to othershotguns of the time, including the Ithaca Model 37 and the Winchester Model 12, it's rather heavy and clunky.
As long as everything looks good on it, I'd not hesitate to buy another 1200.