The PSP Go.
The PSP Go has recieved large amounts of negative press from Online commuters, many boycotting the console completly.
This is down to the following reasons:
1) An inpractical design means long periods of gaming is not possible as the battery runs out after 3-4 hours of solid gaming.
2) If the battery breaks you have to buy a new psp go
3) It costs $50 more than a psp 3000
4) For $50 more you can buy a ps3 fairly easily.
5) Since games are downloaded they cannot be traded in
6) Games must be bought for full price, giving sony a free roam on prices.
7) Many people do not have wifi and can thus not download games
8) Wifi downloading may not be possible due to isp download limits
9) Smaller screen size
10) 16g Flash drive would be filled up quickly due to the space games and movies take up, forcing you to buy a memory card
11) Old charging adapters do not fit the new model
12) No UMD conversion forcing you to buy all your old games again.
13) Many accessories are built specificaly for the go model and thus robbing you of more money.
14) Painfuly slow because of the wireless downloading.
15) Proprietary cables over USB is a complete fail
16) Battery must be full to download anything.. even when in a wall outlet.
17) They still didnt add a second analog stick, fair enough its not a next gen console.. but it still would have been nice.
Sure its more portable and looks cooler but thats about it.. bad business on Sony's behalf.
Goto any online board and ask which you should buy.
All will recommend the 3000 or another handheld unless they are ill informed.