arcam - I'm not sure if any LCD projector can be compared to a properly calibrated Toshiba RPTV (i.e. the ones with 7" CRT/ 16:9 display), the only advantage of the AE100 is the picture size.
What I can only confirm is that the AE100 combined with a Radeon HTPC will give other FPTV a run for their money (picture quality wise).
Some people have reported favorable results with the Panasonic RP-91 or RP-56 progressive scan dvd players but I think in theory, the dvd players with VGA out (i.e. Skyworth 1050p or the Nintaus - all availaible in
www.hivizone.com) will give more favorable results.
The screendoor is there regardless of what source you use but a slight defocus makes it negligible (almost unnoticeable in actual viewing). The FL-D or FL-W filter also helps reduce screen door while removing the greencast inherent in the AE-100 (due to UHM lamp).
I'll be concerned with buying from overseas since you might end up with dead pixels and this is annoying esp. if you know where it is (my first AE-100 have about 3 grouped stuck on blue pixel and the shop where I bought it from replaced the unit). My current AE-100 has no more dead pixel.
In terms of % improvement, I think HTPC is about 10-15% better (noticeable in SW TPM, American Beauty, Moulin Rouge) plus you can tweak the HTPC picture more (I'm using zoom player 2.5). The improvements are better blacks and punchier colors.
Oh and the lamps are super cheap compared to 11HT (around 20,000 yen compared to 50,000 yen for the Sony Lamp). Good value if the 5000 hour in economy mode is true. I hope to buy a 3-chip DLP after the AE-100 (o baka kasing presyo na lang ng AE-1000 young Sharp 9000 by that time). Hehehe. Sana may trabaho pa ako nun.