Keep in mind the funds are executing variations on the same strategy and there are many overlapping holdings across the funds yet the results are different. It should be noted that the new MRGR also has many holdings in common with the other three funds. MNA has lagged meaningfully behind MERFX since its inception and lagged slightly behind ARBFX. It obviously remains to be seen whether MRGR will lag, lead or be right in the middle of the pack. A few years ago I personally purchased MERFX. The idea at the time in going with that fund instead of MNA is that MERFX is actively managed and the manager has more freedom to make qualitative decisions vs. a rules-based index that does not have the same freedoms; both ETFs are rules-based. The stock market cycle may be near an end, especially if "fiscal cliff" fears turn out to be warranted, and this will draw more attention to defensive strategies like merger arbitrage but not all defensive strategies will lend themselves to a rules based index. At the time of publication, the author had a personal holding in MERFX.This article is commentary by an independent contributor, separate from TheStreet's regular news coverage.