I can press 4 together on my Eclipse II no problem, but 5 doesn't work.
didnt have that problem myself
but id still avoide it tbh. Although well built, keys die easy and are not very sensitive (u gota bash em). it gets worse as you use it more. which to is pathetic and useless for a "gaming keyboard"
im not the only one had this problem, seen many other on the net.
you get what you pay for, especially in this case. worth saving for a g15 or the like imo.