If the giga is cheaper than the other 2 then GET IT! While there were differences between the 3 in the past, newer revisions have almost completely removed them.
Toxic - used to be a great card -> overpriced POS
Giga - used to be mediocre -> as good as the others
MSI - hynix memory with unlocked voltage - > slower elpida memory with LOCKED voltage but still the most silent of them all
Go for the gigabyte...