A833 O/D What will it handle?

I have broken 3 of the 4 that I have owned. The M/S O/D gear is very weak. Twice I forgot which box I was running and accidentally speed shifted into it and BAM instantly tore it up. On another, I stripped the M/D teeth right off the input shaft. The last one worked fine for a couple of years. I ran a GearVendors box behind it for a few years. Good splits and double O/D was nice. Eventually I switched to the 273 ratio box still with the GV behind it. Five gears is enough for me, esp with splitting capabilities. All this was/is behind a 366sbm,430ish hp.
--I tore a few clutch discs out of it too. I finally installed a Centerforce Dual Friction(diaphragm type) into it, but found the disc too harsh for street. I put an oem 340 disc in instead still with the CF pressure plate, and shimmed the pressure plate out something like .030. Now I have a slipper clutch. Works great on the street;just blip the throttle and dump it. Just enough slip for smooth take-off from idle and the rollers kick in for performance driving.
--For a while there, it was a pretty expensive learning curve.Drive shafts, U-joints,yoke-straps,diffs.It got sorted in the end and no more trouble.I didnt have all this trouble until I fit 295/50-15s out back. Of course it wasnt really drive-able until at least 275s went on. Even then, it used to switch ends pretty regularly.Now I can toss it around pretty wildly and its fairly forgiving, At least thats what passengers say.Some come back for seconds, most not.
--Going back to your question; I suppose the first 3 gears are at least as strong as the regular boxs.
--I can believe that the M/D failure was a fluke. Be advised though that the ratios are fairly wide. Its not for every combo. Your engine will need to have plenty of torque down low in the rpms.
--Race gear diffs werent the answer for me either. Eventually first gear becomes nearly useless.For street, 3.55s worked the best for first, but 2nd was a ways off(it wanted 4.10s). So 3.91s became the compromise.And then 3rd was a ways off. Thats why I went to the 273 ratio. Everything tightens back up, and the 3.09low lets me run 3.55s or even 3.23s. I highly recommend it.