Unfortunately, I've some bad news. Jimenez Arms was formed from the wreckage of Bryco Arms, which declared bankruptcy after a court awarded damages to someone injured by one of their defective handguns. The LA Times reported on Feb. 4, 2005, that the California Department of Justice ordered Jimenez Arms (which is based in Costa Mesa) to stop manufacturing the JA-9 pistol on Jan. 13 of this year. (The story can be found at:
http://www.latimes.com/news/local/orange/la-me-bryco4feb04,1,5596038.story?coll=...)
With firearms, the old adage "You get what you pay for" is truer than in many other situations. You're not alone, the very first pistol I ever bought was a $50 Jennings/Bryco J-22 that quickly shot itself apart. It's still in pieces in my gun safe waiting for the next gun buy-back program in Detroit.
As for your JA-9, I wouldn't shoot it. The article mentioned "parts coming off" the guns during testing. Considering that 9mm semi-automatic pistols harness the 360 or so foot-pounds of energy the 9mm cartridge generates upon firing to operate the weapon, that's a considerable amount of force being applied to a firearm of suspect workmanship. The last thing you'd want is for the slide to break free of the frame while firing (since when you're aiming, your face is behind the slide and that's where it's heading). At any rate, I'd find the dealer who sold you the pistol and give him a good chewing out as he should have known about the DOJ order to Jimenez Arms in January.