IMO the Metra looks more complete. They provide a little storage slot to replace the display panel that will be rendered nonfunctional with any HU swap-out. It appears to be limited to 1-DIN, though. Speedline offers two kits. One will replace the stock HU with a 2-DIN mount, and the other adds a 1-DIN above the vents, without removing the stock HU. Someone on this forum already installed the one over the vents with a DVD player, but I can't find that thread.
Is it hard to do this install? I installed the deck in my current car, but that was cake, this kit looks kinda complicated, is there a write up around?
EDIT: I saw the instruction manual on the site, doesnt look TOO complicated.
Is it possible to hook up amp and subs to the stock deck?