Depends on how far away you're sitting. Good HDMI players at 1080p upscale better than the Panny, but the extra detail only really noticeable at under 6 feet. At 10 feet you can't really tell the difference.

Well, the Panny's upscaling is softer, meaning less detail but able to hide artifacts very well. Color is also deep. That's why Astro looks good on it.

The DVD players upscale sharper, so there's more detail, but if your DVD is not a fantastic copy, artifacts are easy to make out.

To the layman, the difference will not be readily discernable. Both will look good. Even if you're really looking for differences, you'll have to sit under 6 feet or closer (I do it at 3-4 feet to make out the difference).

If you're on a tight budget, you'll be pleased to know you're not losing out that much on PQ if you stick with your current set-up, not at 10ft+ anyway.

If you decide later to blow a few hundred bucks on good component cables, then that's the time to consider switching to HDMI.