Was browsing for a new set and came across this which has been in and out of stock.
The model numbers are unique to Costco, but when comparing features I believe it is a white version of their top of the line WT7900 Series washer and Dryer (GAS) with steam cleaning in both.
At this price its even cheaper than their WT7800 series which has great reviews and ratings on consumer reports.
The Black version seems to be going for $1899-$2100 in most places so this is a much better deal.
If you need the electric version you can save another $100:
Costco includes installation and haul-away and 2nd year warranty, so the price is hard to compare to other retailers once you add that all in.