You should post this to the instruments forum, and/or to the pianoworld.com website, which I believe has a dedicated digital forum.
You cant buy a piano from picture, and asking advice here doesnt mean either you'll get the piano you want.The best way to buy a piano is to go to a pianodealer and try out alot of digitals, with and without headphones (!) Then you'll see the differences (or not) and will be able to buy yourself a piano that suits you best.
Yeah, of course I know...I actually went to a music store and tried FP-4 and FP-7 myself, but the problem is that I can't sit there and play it for hours to see if it is comfortable to play for a long time.....so I need some advices from someone who own one of the mentioned and tell me what they think about them with their personal experience. Yes, it is true that ones opinion may be diffirent from others and that's totally depend on personal preferences. I just need some opinions and / or feedback from the users so that I can have more insight information.Well, from what I felt by trying the FP-4 and FP-7 for about thirty minutes, I could only say that base on the touch I like FP-4 more than FP-7, because the FP-4 feels more like a real piano while the FP-7's keys bounced a bit after each press......I am not sure if you guys have the same feeling on that....I think I'll go to the store and try them again anyway. By the way, how long did you try the pianos before you bought yours (just out of curiosity) ?