I dont know much about Eizenkot. He brings value with his name and seems to be popular, though by now we all know that success in the IDF does not necessarily translate to success in politics. We shall yet see what his beliefs are (some are claiming his political beliefs are closer to extreme left than center right), and more importantly whether he has staying power and if he has what it takes to build a political base and not just ride on his name. 

I think Matan Kahane joining with Eizenkot and Saar/Gantz is a good move for him and for them. I believe he has enough of a political following and will bring some additional support to the party, and it gives Kahane a good platform for his ideas. I like that he is interested in the religious side of Israel and wants to improve and change things for the better (though plenty disagree that it is for the better, but from his perspective it is). Most parties and politicians until now, all of them actually, preferred to not be interested at all in religious affairs and would just outsource all religious issues to the Haredi parties. I think it is good that other people are actually interested in them and not just pawning them off out of disinterest. 

Interestingly, MK Moshe Gafni (UTJ), who until now has supposedly unofficially blacklisted Matan Kahane warning, supposedly, other parties that if they bring him into their ranks UTJ wont work with them in the future, reportedly said that this is a fatal mistake. Gafni has been floating rumors that if Netanyahu does not garner 61 mandates in the upcoming elections, all bets are off and they could potentially work with Benny Gantz in forming a coalition. Until now all the other parties (except for Lieberman's) have been tiptoeing around the Haredim since this election cycle began, even though the Haredi MKs keep saying they will only work with Netanyahu and even go with him to the Opposition, hoping that they could draw the Haredim into a possible centrist coalition. Gafni is the only one who has said this is possible, and even Gafni himself said the other day, after a talk with Netanyahu, that he wont go to a coalition with anyone else, only the Right behind Netanyahu. So I am not sure what Gafni is now saying the merge with [Eizenkot and] Kahane is a fatal mistake if he wont work with them anyway. He said he wont work with them and only with Netanyahu a thousand times, including just a couple of days ago, after saying once or twice that Gantz is a possibility, so if that door was actually ever open, which is unlikely and probably just false hope, it seems now to be closed.

Overall, Eizenkot and Kahane joining Gantz and Saar, I think, is a good move for them all. We'll see how long it last though. And we'll see if it helps them either form a coalition or prevent Netanyahu form forming one. Likud also courted Eizenkot, so presumably this could potentially pull away some voters Likud was trying to attract.