Alpha is great brass. One of the best on the market today. I would also recommend the OCD SRP brass. I use this for my 22 GT and 6 GT rifles.
Peterson brass in my 6 xc had been excellent.I tried some alpha brass and I have had some problems with alpha brass for a 6xc not having consistent case rim thickness. About 10% of them won't even fit in the shell holder to install a primer. I have a whole unopened 100 round box I will try to return. Probably will be trying peterson or lapua.