We make the Osburn brand. The 2400 is one of the biggest insert you can get. Make sure you take the dimensions of your fireplace to ensure it fits. We also have one of best if not the best warranty. For ex. we will replace the glass now matter how you broke it!
To the gentlemen who has the 2200 insert with the overdraft. I have the same problem in mine. My chimney is 28 ft long and runs inside the house. I've asked sweeps and many industry 'expert' and unfortunately there are no satisfying solutions in the market for an overdrafting insert (no matter the brand). It is dictated by the lenght of the chimney. It's one of those problems that is looking for a solution.
This web site seem to indicate they have draft control devices for chimney. I dont know anything about them just passing along some info. I've sent them an email asking if their devices have a means to automatically control overdraft.
Chimney Damper Source...chimney dampers & downdraft solutions...lyemance & lock top chimney flue damper...round flue dampers