What is this new mod with brass contacts you are talking about?
it has a .36v loss in in voltage under load. that's not horrible, but man that's a decent amount. I may just stick with some higher end mechanicals, as a 3.7v battery would read 3.34...that's a large amount considering some other mods that use brass contacts can be had for $100 or so (one just came out and is on sale) and i do believe the loss would be way less.