If you use the Tekno mount, you will need some metal chassis stiffeners to prevent chassis flex which would change the gear mesh. With the RCM mount, you don't have to worry about this because the motor mount is attached to the center diff. I really liked the Tekno battery tray for the Revo, so I am sure the quality of their other battery tray will be as good. Only problem is that you have to drill 4 new holes. With the RCM battery tray, you can use existing chassis holes which is a huge benefit in my opinion, however I found the Tekno battery tray to be more securely mounted to the chassis, but the RCM tray holds the battery more securely, so each have their pluses and minuses. You can't go wrong with either one though.
Hope this helps.