I used to camp these guys back in the days of my 32THF/NIN16. I could solo them, and I didn't even have Utsusemi back then. The reason I camped them was actually so I could get a Cruel Scythe and sell it...but that never happened(The selling that is. o.O).
I don't see why gilsellers would camp that place, though...it doesn't make sense to me. Either way, if you're 35 or above, these guys are cake. Just watch out for their Dimensional Death WS, as it has been known to lay the smack down on people. :P