I have an 03 Silverado 2500HD. The speakers sound great. The OEM speakers were dry rotted away pretty much and the "seat belt" warning tone plays through them (which I did not know) before these you could hear music, but never the alert time, imagine my surprise when I plugged them in and they started dinging..... Point is, obviously the old speakers weren't able to play that time, even though they still played music very mediocrely.
The only CON I have is they do not come with the spade connectors .... I had to cut my plug from OEM original. Fortunately I keep a pretty extensive wiring kit, but that would create quite a problem for someone who didn't.