My wife and two of our very good friends run the Huntgroup FD-12bullpup shotgun in competition and they have proven to be very reliable. The bullpup is very compact due to the design, and after breaking them in with about 200-250 rounds of heavy hunting loads( believe me,,they need to be broken in) they will cycle anything from low brass target loads to slugs with no problems.
If you check the serial number before you buy, be sure it starts with OD###x, allegedly this means they are inspected by an O’dell employee in Turkey before being accepted. O’Dell are also excellent to deal with on warranty if necessary.