I think the old Netgear (I THINK WNR802 rings a bell....) would probably limit speeds, although I chose not to go down the superhub road in the end, because I'm possibly moving house to a non-VM area (

)
Assuming you mean user/pass auth, just out of interest, do you ever check for hack attempts?
I suppose I could go quite tech and get a firewall inside a virtual machine in my little server and route the whole internet connection through that, but I don't know if I can be bothered.....I think like you say, a username and password might be an option