32pw9551 - upscaling dvds and HD material

Hi

I've just aquired the 32pw9551 32" crt philips tv with hdmi and component inputs. I've been watching dvd scenes in standard interlaced and progressive scan mode through scart and component cables from a marantz dvd4001. Its funny but so far I do believe I prefer regular scart 576i with pixel plus enabled, although many people have spoken very positively about the prog scan mode.
For your interest, I've had the 32pw9509 set too, but I remember that I prefered pixelplus2 turned off, as the resultant picture became very video like and sort of artificial. This was both in pixelplus, movieplus and pixelplus2 mode. I find this to be different on my new 32pw9551 - here the picture looks a tad sharper with pixelplus but without any apparent sideeffects. Its a bit strange to me, but maybe they tuned down the effects on the newer version or something. Naturally I've been running the tellys with sharpnes at 1 and all digital processing turned off as it is generally advised to do. Well I thought you might find that bit interesting.. however, my real question is the following:

Can anybody with the 32pw9551 tell me if its worth upscaling regular dvds and feeding it to the telly with a hdmi cable. Its just that I don't have a cable to test it myself, and want to know before I spend the money. Does upscaling to 720p or 1080i result in a markedly improved picture or is it more or less the same??

Also, if anyone has tried feeding it a true HD signal, from a hd-dvd or a blu ray disc, does the full effect of HD shine through on this set? Can you tell the difference between regular uposcaled dvds and the HD discs? Im sure its quite easy to tell the difference on a projector or a flatscreen, but I was wondering how big a step forward it is on this "regalur" telly
I'm asking cause I'm considering buying a ps3 for dvds and blurays.

Any advice is much appriciated
Thanks