Your talking about SAS so you are far from thread jacking.
I love my D30 SAS, best thing that I have ever built and put into any vehicle. I love how it performs and what it does. I like how the simplicity of it is too, say change a bearing unit on it. The after market on them is nice in size so not to hard to find parts for them and there is tons of info on how to fix them, upgrade, etc... for them too. As far as the strongest, far from it, but easy suites my needs for what I do with my truck, and I have sewen these been through some hell too and servive. Just all depends on your driving. Ya the D35 is 99% bolt in but i had got my axle for free too so went that rought but was wanting to do a D30 swap anyways (and 2 weeks later one landed in my lap).
Many guys say dont do a D30, if doing a SAS, do it with a D44 at mininum. I wonder why I would need to put a fullsize truck axle under a compack truck that weighs much less and doesnt have the engine of a fullsize? Now I know some people do have fullsize truck engines in their ranger but for those who dont, why would you really need more?
One thing that i do like about the D30 axle is the 4 link points of the axle, and combined with longarms, you can super fine tune your axle under your truck too. Now this can be done with a D44 as long as you put the 4 mounting points on them and not run radius arms, and yes Jeep D44's are like this and sold this way, and I would rather run longarms the radius arms any day.
Above all it comes to how much money you are willing to spend and time into doing this and TTB is the same way. I just dont like TTB because of it needing tunning non stop (seems that way). And the after market for them doesnt seem to be as big and theres not as much info on them either plus many shops arent to familiar with tunning TTB either, let alone a modded one and alot of them wont touch them either.
One question you have to aks yourself is, what do you use your truck for and that will decided it for you from there.
If I got another 4wd ranger, i would end up doing the samething to it hince why im looking for a 2wd.