If you plan on keeping your axles for a long time or run really large tires, stick with a full case locker like a Detroit. That being said I have run a LockRight in the front of my TJ with 35's for about a year and a half with great results (knock on wood). If I was planning on keeping the D30 I would have gone with a better locker but the LR has served me well and they have a good warranty. I did have one about 5 years ago in the back of a YJ that I bought used, stripped some teeth on the gears, sent it back and a few days later had a brand new unit. Never had another problem since. Can't really go over all the pros and cons in a paragraph but let me know if you have any more specific ?'s.
BTW, do you have trac-lok or another limited slip diff in your jeep? Can't use them if you do.