3 way as in dynaudio 360, DLS 6.3, or somthing similar?
if so you wont need the memphis bell at all. you will only need two channels that do 100~150w and a nice mono amp. ie- 3 channels.
if you are doing 2way+active - then maybe you could utilize the memphis. from what i recall the memphis does more power and has more channels - but id rather have the DLS built amp if i was doing the 3way with the dyn setup, i just wish it was a BIT more powerful.
but unless you plan on spending $500~1000 on comps, i doubt you are going to want the DLS amp and will opt for the memphis.