They are not needed for most people.
If you do decide that 1350's are needed, they should be for the rear, as this is where most of the stress is focused when wheeling.
I did 1350's rear and 1310's front.

 

I've considered 1350s for the rear and 1310 for the front. How's that set up work for you? And do you have the JE Reel shafts or something else?

 

You should try and locate driveshaft manufacturer in your area. They can make shafts with just as high quality parts and strength for much less.
There is a shop around me that does shafts, and when i replace i will be paying $200 an end and they will be just like what JE Reel or Tom Woods offer with the same quality, just not paying for the name.

 

x2. I bent my rear driveshaft this past weekend when I high centered on a big rock. I can drive it fine but it vibrated around 40MPH. I went ahead and ordered the front and rear 1310 shafts from J.E. Reel, that way I can easily use my stock shafts as trail spares if I ever need them. I spent almost $700 including shipping on both the front and rear shafts. I'm pretty comfortable with the 1310's even running 37's.
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Just wondering, is it very difficult to install your own drivshafts? Is it basically bolt on or do you have to get certain angles and what not correct? Better to get it done perfessionally (aka OFE)?

 

Well....I guess it works pretty good so far. I haven't broken either yet.
I run Tom Woods new shafts. They are excellent products and very easy to install!

Again....for the average wheeler that is doing moderate to difficult trails, the 1310's in front are plenty strong for anyone. I'm running 37's and doing some pretty darn tough trails and still feel that the 1310's are plenty.
If you are driving like a maniac and bumping your jeep really, really, hard(which 98% of the guys on this site are NOT), then you might want to go with 1350's in front. That being said.....with a big, heavy 4 door wrangler, with a 4:1 transfer case, locker, 37's, etc, in the rear, I would stay on the safe side and get the 1350's for the rear.
It makes the sense for most applications and will save you some money.

 

It is very easy to intall the drive shafts and new flanges.
It seems intimidating but there should be no fear.
As long as you have a two or three arm puller, you can have the flanges off in about 30 minutes. Once they are off, it is simply a bolt on affair.

 

How much did the Tom Woods shafts run you if you don't mind me asking? I have a 2 door with 3.5" lift so I'm sure mine will need replacing in the next few thousand miles.

 

About $1,200. This was for 1350 rear and 1310 front.
One of the best parts about Tom Woods is that he makes each set to your specs, rather than just a basic application. You have to measure and get him your numbers.
Once you place the order....THEY ACTUALLY SHIP THE NEXT DAY! Two days later, my shafts arrived at my door step.
He gave me free shipping.....and to fully polish them to a shine and apply a clear coat.... it is only $15 more.

 

And that included everything you needed for installation? This is tempting. I could have new driveshafts before the offroad expo!!!!