Best: My first rifle, and the one that got me addicted to milsurp. A finn refurbed 1917 Westinghouse M91 Mosin. I had so much fun searching up and down about all the markings on that gun, and have learned so much in the process. I've spent a lot more on guns since but none have brought me the joy of discovery that it did, although an 1853 Snider Enfield came close. Also snagged an original trenchgun for a great price off of the EE many, many moons ago. That was a happy occasion for a gun I would never normally be able to afford. Picked up a hi-power with most of the decal, it cost me, but it a very proud addition to my collection.
Worst: A TT33 tokarev I bought from a member here that was beat to #### and wouldn't feed more than about 2 rounds in a row. Then the mag would stick in the gun. None of this was mentioned at the time of sale, very disappointing. Hated it, and felt burned by the whole experience, and sold it at a loss with full disclosure. This was before cheap and abundant toks were available, so I jumped on it for the rarity, but it was just a turd. Fortunately my experiences with the firearms community have mostly been far more positive, but it's sad and sobering to realize there are some real ####heads amongst us. Speaking of good gestures, I also had a parts bin SKS I bought from SIR. The barrel fell out, but they replaced the gun with a cherry Chinese one. Great service.