Lot's to comment about here.

For reading purposes, check out this article comparing different 60s for the JK.  Just note this article is a little older.  Some changes have been made: http://www.mikesjeep.com/artic.....-shoot-out

As for Dynatracs, they have always been a top tier company that has had a premium price point to run their products.  American made with American steel (If there is such a thing)  For a long time, they didn't offer 35 spline outers.  That was an upgrade that costs more $.  They came out with their the new package deal to compete with the UD60s.  It's been really great for us the consumer.  Dynatracs are great axles no questions asked.  Just really make sure you don't get caught up in upgrade up charges and pay attention to what you are getting in the details.

UD60s changed the market.  They haven't been out long and had some changes that have been a work in progress.  They come with much larger brakes and their own caliper unlike Dynatrac - (reuse old calipers but get bigger rotors).  You can find them complete ready to bolt in with driveshaft options which makes them a weekend project.  35 spline all the way through.  Their is a lot of debate on the e locker. 2 pin vs 4 pin.  Dana has done extensive research on the 2 pin design and they say that if you can break the 2 pin e locker, you need to move to a larger axle than a dana 60.  The 4 pin design hasn't been able to pass dana's testing yet... Another greta option as Kris has mentioned is that your current drag link and tie rod will swap right over and you won't need to buy a new set.

Currie, like brad said I wouldn't buy unless you plan to stay on 37s or go RJ 70 but I still wouldn't run their unit bearing and would rather run f350 factory unit bearings.  High pinion rear is a slippery slope.  Huck with his hemi and 40s broke 3 rear ring and pinions due to gear deflection in their rear application.  This is why they have come out with their new load bolt VRX 60s design which costs more money.  Basically it adds a bolt to pinch the rear ring gear so it can't pull away from the pinion.  Mostly seen in drag racing applications.  Currie can make nice products but their unit bearing is what drives me away from using them. 

Teraflex is interesting.  There isn't a lot out there about them.  But I think they make a nice product.  It is the most complete axle set you will get.  Comes with calipers and their own tie rod and drag link.  The knuckles are a one piece design.  No steering arm to come loose or snap bolts with which I think is a nice touch.  Full Float rear design as well as 35 splines and multiple gear choices.  They have a high pinion rear, which again will potential give you rear gear deflection.  If you wheel like a Toyota guy, I don't think it could be an issue but if a hemi is in your future, watch out.  The nice feature that I like is the rear full float and front hub are all standard bearings that you can get at any auto parts store. 

We are working with 3 of the top mentioned companies and I hope to bring you guys more insider information.  I'll keep you posted.

Custom width is really only an option with Dynatrac and Currie.  UD60s is set at 68.5 and Teraflex is 67" or 70". 

I think the old school train of thought applies to doing the rear first because the rear axles weren't that great and generally, the rear gets more abuse than the front.  

The JK front axle has it's weak spots no doubt.  Many more than the rear.  But I personally think the rear axle is very strong for the most part.  I've thought a ton about just keeping my rear axle and upgrading it.  The only problem is if and when something breaks after all that money spent, would I wish I would have gone with the 60.  

Eddie from Wayalife did the 60 front first and wheeled with too 40x15.5 on the rear 44 for about a rear before he broke the ring and pinion in this video. Time-9:40

He has a long list of trails that he did with that setup.  But ultimately he ended up with a 60 and then later an 80 after a motor swap.  If you have no intentions of going to 40s.  I wouldn't go 60.  Unless your my brother Jeff...

I wish the tire market would bring more 38" and 39" tires to market. I think there needs to be tires between 37" and 40" for the built JK application.  

If I was building a TJ or LJ, I would have a hard time not swapping in some JK 44 axles and running 37+ tires on them.  Wheel them until you have hosing issues then swap to some fancy aftermarket housing.  

If you want ultimate JK strength, just go RCV fronts and rear.  It will only cost you about $2800 for all the axle shafts but you will get a lifetime warranty. 

Also, Rob in the club ran 40's on JK axles for several years before he just swapped over to 60 and 14 bolt.