the t800.4
150x4@4ohm
150x4@2ohm
200x4@1ohm
the t1000.4
250x4@4, 2 and 1ohm
as for why rf
1 is warranty, and i can claim local and dont have to ship back to usa (costing more the item itself)
2 price, when your dropping 120 just to freight 1 set of speakers, you dont want to be shipping...