I have all three versions of this pistol in my collection starting with the first model marketed by Ordnance Technology. Magnum Research bought them out and updated there model to the Lone Eagle and quite production in 2001. Competitor Corporation bought them out and still makes the pistol in a much improved version. All versions shoot accurately and have enough mass to handle the heavy recoil produced by many chamberings. The price on the MRI pistol is reasonable but your limiting yourself when it comes to repairs and other barrels/chamberings. Don't know is MRI has parts and barrels/chamberings available or if you would have to acquire them from eBay/AuctionArms/GunBroker sites.
GunBroker currently has a Competitor Pistol in 307/308 listed selling for around $100 more with the S&H etc. Considering the updates, new features, availablity of parts and different chamberings this would be the route I would take. When you rotate the breach to eject the shell you also cock the pistol on the latest version. This does away with the side cocking lever. It has two safeties--one on the breach and one on the trigger similar to the Glock pistol. Pistol grips/stocks are available made in hard rubber/plastic and laminated wood. Personally I like the laminated wood grip the best for fit, feel and comfort. Barrel changes are easier and faster with the last version.
After examining all three models the last model has been improved with considerable engineering expended.