Is it worth it to install a locker in my Dana 30?
Absolutely, especially since you're surrounded by dry desert. It'll make a HUGE improvement in rocky uneven terrain, they're night and day improvement over an open axle. They're a good choice for the front axle when the rear is a Dana 35 which in stock form is not strong enough for a locker. But if you have a Dana 44 axle in the rear you'd be better off installing your first locker into the rear. For the rear avoid "lunchbox" lockers as they are weaker than a full carrier locker like an E-Locker or Detroit Locker, and lunchbox lockers are very poorly behaved when in the rear axle for a daily driver. Full carrier lockers can be very well behaved, especially if they are a selectable like an Eaton E-Locker or ARB Air Locker. A Detroit Locker is an automatic and much less expensive, I loved mine. But it takes a day or two to learn how it likes to be driven so it is well behaved which is basically nothing more than using neutral throttle when making turns... neither accelerating nor using engine braking through turns which locks it up hard making it crow-hop through turns.
In the front a lunchbox locker is very well behaved when you're in 2wd. It doesn't lock up hard until you shift into 4x4. Though some lunchbox lockers click and ratchet while you're making turns. They'll make some people close by think you have an axle problem. But that clicking and ratcheting is not a big deal if you don't mind it. There is one lunchbox locker called the No-Slip. Made by Powertrax, the No-Slip is silent through turns, in fact its presence can't even be detected while you're in 2wd. I had one in my previous TJ and loved it.
The only thing that is recommended for the front Dana 30 if you want to run 33's or 35's is to upgrade the axle shafts to chromoly steel. Installing a locker can double the load an axle shaft sees in some conditions and the "ears" on a front axle shaft that hold the u-joints are not strong enough for 33's or 35's once a locker is installed. Upgrading the front shafts to 4340 chromoly like from
www.revolutiongear.com will beef it up so 33's and 35's will be no problem even for your tough local desert terrain. I broke a front axle shaft with my No-Slip locker on 35's with the OE factory shafts but I had no more problems after upgrading to chromoly axle shafts.
Installing a locker into the front or rear will make a very dramatic and significant night and day improvement in your TJ's offroading ability. Just avoid installing a locker into a stock Dana 35 rear axle which, again, is not strong enough for a locker.