Aeroflot 777 seat width?
 

The "normal" coach seat width on a nine-across 777 is 18.5 inches, with 17 inches on a 10-across. Aeroflot's seat map shows that they have 10-across seating, but SeatGuru says the seats are 18-inches wide. How is this possible? Narrower aisles? I can live with a 18-inch wide seat, but not 17 inches.

Given an inch, take a mile :p

Its narrow. I personally have not flown SU economy intercontinental before on the 77W, but strolled back there in between the meal service to stretch my legs.

If you're concerned about comfort, Aeroflot has a decent Premium Economy on the 77W which can be had for not much more money, at booking, or sometimes at check in, it available. Generally its better to outright buy into comfort in advance. Less problems to re-ticket, prices about the same anyway, and you're guaranteed a seat.

If price is an issue, try to find the A330 aircraft. I've flown that before at the back, to Sochi from Moscow. Wider than the 77W.

The Y seats on the 77W are quite narrow, I personally haven't flown in it but have strolled into Y as well and I would say it's probably 17 inches.

As suggested above, W class is reasonably priced, earns a lot more miles and gives you a good chance of an upgrade if your plane is swapped with an A330.

I'm probably going to skip Aeroflot. I was primarily interested because Delta has 30,000-mile one-way redemptions to the Baltic states on Aeroflot. Most of the really cheap redemptions require an eight- or nine-hour layover in Moscow, so it's a pretty hellish trip, particularly if one isn't starting at JFK.

While seat width indications are somewhat helpful, they only reflect the designed width of the seat itself. In the end,
The actual shoulder and hip width of the passengers, multiplied by the number of passengers per row is more important (in economy).
If you are on the wider side, get premium economy or business. If you are normal sized and traveling on a tight budget, try to get into row 17 a/c h/k (it's difficult even for Aeroflot bonus gold members).
Finally, i much prefer decent legroom over shoulder space. Aeroflot offers a good and affordable economy product. However, I'm grateful for every opup i get.