i also own p320.
1. no
2. no
3. no
4. now here the real story begins do u really need 8 gb or u just want to try tht ur phone does supports 8gb sdhc cards .if u need thn its ok ...go ahead n if u only want to try thn let me tell u tht this phone supports even 16 gb sdhc cards(maximum available in market i think)
copy pasted frm gsmarena.com
"phone supports SDHC, so do not worry abt the max memory card capacity it supports... it supports high density cards.. it can support 32GB or even more if it is available& if it is a sdhc.
* Make sure u ask for a MicroSD. (Telling micro is a must or u end up buying bigger one which wont fit)
*Then make sure u ask for SDHC.It means its a high density card.
I am using a 8gb class 2 card and is doing perfect..So do not worry abt max capacity, it supports any capacity SDHC card u throw at it...
link for ur refrence
http://www.gsmarena.com/asus_p320-reviews-2347.php