Re-intro and humbly asking for experiences

Hello, I recognize some of you from other boards and maybe when I was here last.  I have 5 boys, 4 with my ex and my March baby with  dh (his first).  My oldest, soon 16, lives with his father primarily.  I do EOW, and midweek visits, I have primary physical custody of my 14(almost), 12, and 11 year old and their father does EOW.

My reason for re-intro is this, my ex is asking for my 12 and 11 yr old to move in with him.  I am trying to think about what is best for them.  It kills me to say that he may have a few valid points- mostly financial.  My dh is ill and not working.  He has been unemployed for a year and has filed for disability.  We got pregnant right before he was hospitalized for the 3rd time last year.  Our finances are a mess, basically we are broke and struggeling to make ends meet. 

My ex does very well and can financially support the boys better than I.  My oldest son has done very well living with his father.  He is an excellent student and very independent and mature.  His father works long hours and travels atleast 1x a month.  I am concerned about my younger boys not having as much supervision at his house and yes I am scared as hell of being viewed as a failure of a mother if Iagree to him having them.  The other major concern and more valid is that my 14 yr old and his father do not get along at all.  My ex is very demanding, not necessarily a bad thing, just hard to take for some personality types.  Ex is Army, he is the prototype type A, non emotional, all work no play, etc type.  How will my 14 yr old feel if his brothers all live with their father and he doesnt?  I just don't know how to do what is best for them all individually and it make sense for all of us as a family too.

I'm struggeling to say all I want to say but this is long enough.  I am just in a hot mess of emotions today.  Just looking for ? vent someone that has been there done that, etc.