Skip AI, The JLK bullets have been around for some time, but ownership changed recently. I know several people who brought them down here to Oz, and had varying success with them. The link to their website is:
I have not tried the Berger 115 VLD in my 25/06AI, but have used the 100 & 115 Nosler BT, as well as the Wildcat 125 ULD and 130 BCFBHP.
I endorse Kirby's comments about the Wildcat bullets, as I too have found that they are great, and Richard (the owner) is an even greater bloke.
My experience is that the heavier high BC bullets, do not shoot quite as flat out to about 300 yards, but catch up quickly after that. However, the real benefit from using them is their performance in the wind, and as you would know Oz is a windy joint. Regards, Brian.