I'm not familiar with these speakers but if they are current hungry the Threshold will do just fine. Don't forget that doubling the power only buys you an extra 3 dB.
200 to 300 wpc amp revised question
i forgot to mention in my previous question that the reason for leaving the threshold s200 at 100 wpc is that I purchased von schweikerts vr4. although i haven't even hooked them up to the threshold yet, i was told they would need 200wpc, actually in an email from von schweikert himself.