For all-around general purpose (property protection, range, hunting) would you rather have an AR15 or AR10 if the cost of the rifle was the same.

AR15 - any 5.56 upper or AR10A4 carbine, both with FS not muzzlebrakes.

5.56: AR-15

.308: HK-91

HK 91 is too heavy and not accurate.  

Id say 5.56 but it depends on the size of game you want  to hunt.  Perhaps a 6.8mm uper would suit you better for general duty?

I'd rather have .308 and prefer the Bushmaster 308 16" carbine to the AR-10.

AR-10, Then you won't have to worry about getting a larger caliber upper.

Buy Both...I did..

For defense against people AR.223 is fine.If you want something that can be used as a long range rifle and that can take large game as well as effectiveness against people the AR10.If you have an AR but want a long range rifle without having to adopt a different weapon then AR10 as there is 70% parts commonality with an AR at least the armalite models.I know other AR10s use AR parts but I dont know if its less or more than armalite.Now with M14 mags cheap again I would get an armalite AR10 over the Bushmaster .308 but for ARs I have all Bushy and one RRA and armalite.An AR10 is an all around rifle except when it comes to needing to carry a lighter rifle with alot more ammo this is where >223 AR is better.

SR-25 is the King Cong Ding-a-Long
That rifle I will never sell