I have a Detroit Locker in my 8.25 and an Aussie in my d-30. My XJs on 35s w/ 4.56s. I drive 35k-40k a year, and 1/2 those miles are pulling a heavy mid sized trailer.
The front you wont notice on the street with a vacuum disconnect front end, if you dont have a vacuum disco then get a selectable in the front.
The rear Detroit is a great locker. Mine been in the Jeep for 4 years now. You hardly notice its there unless you really get on it around a corner, then the inside tire will chirp. It does occasionally pull the Jeep sideways when it engages/disengages, but nothing dermatic. You just have to learn to drive a little different with it. My only complaint w/ my Detroit in my case is when pulling the trailer trying to merge into traffic it is sometimes hard to pull out from a stop into a busy street, simply because you have to give it a little more gas, and it loves to spin those 35s in this situation.
Im also really hard on my junk, and Ive only have an issue with the Detroit once. I sheered a shaft and it took out 1 side of the locker, but I was still able to drive 150 mi home at 70mph.
Personally Id go with a noslip in the rear and a selectable in the front if you can afford it or a lunch box if your penny pinching.