I'm looking to purchase a high end spotting scope. I'm kind of torn between the swarovski 80mm or the 65 mm. I was just wondering if the weight difference was really noticeable and whether or not the low light capability was that much better with the 80mm. I was also wondering if the HD glass was that much better then the non HD? Any insight on these spotting scopes would be very helpful, because this is going to be a once in a life time investment. I will be using the scope for hunting.. sometimes packing out a couple miles and sometimes just spotting out of the truck.