need help deciding tablet size :S

[EyeB]

I just saw the samsung galaxy player 4.0 and 5.0, with those and the galaxy tab 8.9 and 10.1... with all basically the same but different size

Which size have people found to be most useful? Mind you I have an ipad and don't use it very much because of it's size... but what about the smaller ones? 4"/5"/9" tablets? I mean I've had an evo for a while and thought it was a bit small so that rules out the 4", so I'm left with the 5" and 9" size... There's also the 7" tablets, so I'm not too sure which ones to pick :S

I'm basically wanting one I can grab from 1 room to another and pull up articles. I found the ipad too big to "grab" and too big to hold for games :S at least not without sitting down to support it with something (ie legs)

I know people will say it depends on preference, but I'd like some input from people who actually have these to give advantages of the sizes and why they like it :S

edit: another thing i'd like to use on it is gps, i know my TP2 can do it, but I'd like something a little bigger. I do have a garmin navi but that's bulky so if a tab can replace it then great. Also why ipad is too big, can't mount it in car and see past it to drive

edit again: forgot to point out, but the reason I consider these instead of an actual phone is with voip I can make calls, and without the radio, it seems like the battery life is a bit better than the phone counterparts (don't qoute me on this though)