Purchased tickets in 138 for the New York Jets game last year and Qwest Field (I still call it Qwest Field) was rocking that day. Seats are marginally comfortable and give you the luxury of being on the sideline while also having the ability to see the plays in the North endzone too. It's a Charter section which basically means you can expect to pay out the Wazoo for tickets but if you've got the mind, it's well worth it. It's already going to be an expensive day even if you're sitting in the upper level after factoring in food and parking.
To get to these seats, just enter through the West entrance in between the Seahawks Pro Shop and ticket office. After your tickets are scanned, if you just walk straight ahead, you'll be right outside of your seats. You can't miss it, it's that simple.