We had our staircase refinished in August 2013 - Including bannisters & spindles removed, painted and reinstalled + carpet removed from risers and treads, then painted and stained. Matt and his partner were always on time and the cost came in on budget. They also recommended against 2 stains we'd chosen which would have negatively impacted the look. We're very pleased with the outcome especially as the dust and intrusion, while always there, was far less than we'd expected.
If you're considering a similar project as ours remember that builders carpet covers a lot of things including noise, creakiness and wood ans stair imperfections so when you remove it the end results will never be perfect.