1. Yes a datel tool is basically a pandora battery
2. Yes you will be able to do everything you used to I believe with no probs (as long as you own the original)
3. If you have a tool battery and magic memory card made, if you accidently brick it, you can unbrick it with them.(just press x instead of turning the power off when the update has completed.
4. I use a 512mb for the pandora kit I have, I use a hotwire system launcher for psp/slim.
I have two 4gb cards,which I use for my single and double disc games, and one 8gb card which I use for my 3+disc games and avis of my dvds
You can get official sony ones from ebay cheap now, 2gb for a fiver del, 4gb for a tenner del, 8gb for about £20 del.
Finally theres some useful guides and info here:
http://www.avforums.com/forums/showp...&postcount=564
& here:
http://forums.exophase.com/showthread.php?t=3780
Hotwire info and buy here:
http://www.bargainmemorycards.co.uk/...-slim-hot-wire
&
http://www.amazon.co.uk/Datel-Direct.../dp/B0013IVHO6
Hope this helps
tris