RE:AGB vs TMRI own both companies and am a big fan of AGB because of their execution. Low costs, using simple proven design, not biting off more than they can chew. The drawback with them is their lack of reserves. (low risk, less upside)
TMR is the opposite, world class deposit with huge exploration potential but high costs and terrible execution (everyone in the mining world saw the plant issues coming when they saw the Gekko design...). However, the gold is in the ground and eventually someone will be able to mine and process it efficiently. (higher risk, higher reward)