We got naff all with Alaska (Horizon) Airlines.
They even charged us excess baggage (Mrs Globaste was a Gold at the time and I was silver) because our single bag between 2 people weighed 1.2kg over the 23kg limit. This same bag weighed 23.4kg when we left heathrow and had the same items in it.
I took a picture of the scales readout and sent a rant when i got back.
On a separate note, Horizon have a great cabin crew. I think they are an all Q400 fleet so I wouldn't worry about getting priority boarding anyway. Just get a seat near the back and you get less vibration noise.