Cross the MX-150 off the list; it's not in the same league as the other two subs.
Even the original driver 20-39CS mopped up the floor with the MX-125 in the below linked Nousaine comparo.
And the MX-150 and the MX-125 are the same basic sub, except the MX-150 uses the "Headroom Maximizer" (uhh....yeah) to achieve THX certification, despite having the same amp rating of 150 watts continuous. I wouldn't expect the two M&K's to perform much differently in standardized objective testing.
http://www.svsubwoofers.com/news_subcompare.htm
