Get faster with the dan brown method first, (about 1.5 mins), then learn fridrich.
Have you tried looking at dan's "how to get faster" tutorial?
You will be surprised how fast progress goes,
I was at 5 mins for a day, then 4, then it took a couple more days to get three, then two, and eventually i was averaging about a minute with it.
If you have a bad cube, i suggest getting a cube4you DIY cube.