I have polarg amber 1157 dual filaments. I had them when i was into my clear corners, but now they're just behind the stock amber turn signals. I have an adjustable blinker thingie, so sometimes i blink them super fast, but mostly slower than stock, but they've lasted me more than a good year and a half, not to mention my alarm is hooked up to my parking lights, so they blink each time i get in and out of my car. they havent burned out, and they're pretty bright.

as for your lights not being so bright, i remember when people used to cut the grounds to their turn signals, just so they would blink faster, but at the cost of them not being too bright. dont kno if that helps but good luck