As part of Shadow Stalkers sponsorship deal with JD Airsoft, we have borrowed a number of TRMR grenades, and have utilised them at Urban 6 and at Skirmish Mansfield. A number of us were initially sceptical of the use of BFG's, especially with the drills of retrieving them!
The TRMR is the same size as a 40mm grenade so they fit in existing pouches, which is a bonus with existing rigs. They are extremely well made, and come in two parts, the lower section which houses the charge, and the upper section that encompasses the safety mechanism.
The two things that stood out immediately was the speed of reloading the charges, it took seconds after some practice, which in a high intense environment such as Urban 6's 'The Block', is a massive advantage. The second thing is the simplicity, yet speediness of the safety mechanism. It takes a single twist of the upper section to expose the red band, and unlike other BFG's, its just as quick to reset it as safe (a major bonus if you change your mind!).
The TRMR is an impact grenade, and being trialled in buildings, it never failed. In the field through a whole day we only had two failures due to soft ground, so not a bad return!
The speed of reload and the practicality of the safety mechanism has changed a lot of minds in the team, and its become our favourite method of clearing building, even though the issue of recovering them can still be an issue.