I've used Zoltech for new engineered hardwood flooring throughout two houses now (both with the same flooring because I loved it so much: Kentwood Kalispell in Brushed Oak, pictured here).
The owner Zoltan is a really great guy. He'll come and do the quote for you but isn't onsite for the work - not a problem because his team is superb. They aren't the cheapest by any stretch so one star removed for that but they get the job done right, the first time, and they are quick to respond to calls and resolve issues. I personally would rather pay a little more than some of their competitors to know that I'm getting an A+ job - floors are not something you want to have to re-do because of poor installation or change with trends.
Working in the real estate industry, the biggest issue I see with flooring is poor sub-floors. It breaks my heart to see gorgeous, new hardwood with dips and "soft spots" because the contractor hasn't taken the time and care to ensure that the sub-floor levels out any wonky areas and is thick enough for a good feeling underfoot.
Zoltan's crew does wonders - even in my last home which was a total gut-job Victorian with the most uneven floors I've ever had. They came out as close to perfect as you can get a century home.