Lunch box lockers are the lower end of the lockers, most work just fine with out issue. The Aussies are a good choice for a lunch box style locker, I have installed several different brands and the Aussie went in easier and seemed to be of higher quality. I run a Lock Rite and have not had one issue out of it.
The Dana 30 is not that bad of an axle and can be wheeled with out to many issues, Now the Dana 35 is a different story. The Dana 35 is unpredictable and undependable, I would highly recommend not putting a locker in the axle. If you stuck wheeling it, keep the tire size under a 33'' tire and keep the axle open. When wheeling it, the sudden traction will kill it, wheel bounce will also end your day with it.
I was in your position years ago asking the same question and I went ahead and locked the D35, first trip out after the locker and in ten mins I broke the D35, driving up a embankment. I put $280 (plus shipping) in a Locker for the D35, which I sold for $150 (less than 20 mins on it). I have $650 in my Ford 8.8, which is on the cheaper side for a swap, But the fact that I don't have to worry the whole time I am wheeling is worth it. I just wish I hadn't spent what I did on it. But the locker install, I already had replaced the Ring Gear due to the spiders busting and getting into the gear. So I put $300 - $400 in it before wising up.
Currently I run a Locked Dana 30 / Limited Slip Ford 8.8 combo on 35s and to me its a good set up. Looking to lock to 8.8 when I can.