the weld on is most likely stronger at the connection points which is always a huge plus. but the bolt on has to ability to be removed. overall id say go weld on for the strength
Why not get the struts? $50 vs. $200+ then the cost of getting your frame powder coated. This way you can see if you like riding a hard tail, and save some dough to get it done the way you want, if you decide you like bustin yer kidney's.
I have not heard this disscussion in years!! Didn't think they made the hardtail sections any more,I always used the weld on,but you can use the bolt on and weld it up,just be sure of who does the welding and linning it up two critical areas.Good luck.
If you really want a rigid rear end, I would buy struts until I could buy a whole new frame. I skipped the strut part and just saved my pennies until I could afford my Flyrite Smokin Gun.