Need your intel on which whisper to buy.

[mdh21225]

Want to purchase an Ar15 whisper. I've seen uppers at model 1 sales 16 car w/ 1 in 8. They will have them in next week. Any body have one? I will be using an AAC 762SD can. Where do you suggest I get one if not model 1 sales. Theres is about $375. Does it need an adjustable gas block?
Also were should I get 300 dies? Also I've heard people talk about 240gr Sierra hpbt, is this a 308 bulley or something else.

Thank you for your time,
mdh21225