ISX15 exhaust brake question

I'm in Canada with an ISX15 2250 and considering putting an exhaust brake on my truck.
My variable turbo is removed from the truck and even in 2nd stage...my Jake is terrible.
We haul heavy (about 150k pounds) and as it is now...it will not hold the truck back at all. Shows maybe 5lbs on the manifold pressure gauge.
Anyways, I've checked out Blue Ox first. They don't have suppliers in Canada but will ship here.
I also checked out BDDiesel but their exhaust brake only goes up to 4"...and I don't like the idea of putting a restriction in the exhaust (5" down to 4" and back to 5"). Also, it is set for 65lbs of back pressure which seems like alot to me....but maybe I'm wrong.
Has anybody used a blue ox or other exhaust brake?
Did it help much...especially at heavy weight?
What's the max back pressure that a guy would want to see on a 2250 ISX?
Thanks!

 

I'm on Rawze site sometimes. Problem there is if you happen to do something that he doesn't agree with (removing VGT) then he'll jump all over you. I have no problem with somebody having their opinion...but it gets almost nasty sometimes...lol.
But yeah I talked to the guy that did programming awhile back but I guess he doesn't do it anymore. Pretty sure he left the forum.

 

It sucks empty too. But I took off the VGT...so 3rd stage is gone. Just 1st and 2nd....and they're way worse than I thought it'd be.
I have a 2250 and a 2350 both VGT removed and both have terrible jakes now.
Just looking at options....exhaust brake vs cam swaps

 

I'm going to try a cam swap. Doing a rebuild right now and need a cam anyway so might as well give that a shot.
I have an exhaust brake behind turbo on another truck... western star with a Mercedes engine and it's pretty weak for this trailer at only 100k pounds...