A DP34 switch is necessary to see all satellites from a superdish purchased from E*. (one of its dealers if you can find someone who has them) A DP34 switch comes with the SD kit. You can build your own superdish as some have done and could use a SW64 with a SW21.
And how do you hook up 3 lnbfs with a switch with only 2 inputs? To get the majority of the content he would need 119 and 105/121 assuming he just had AT60 and locals requiring the SD, but just saying he only needs a SW211 is misleading. Also if he had DP lnbfs already, a SW21 won't do anything for him.
OT: Is it more proper/correct to say lnb or lnbf? Both get used interchangably.