without reading any previous posts of yours I would say it depends on what your final goal is. a MII front end has fairly short control arms so if you are looking at a lot of suspension travel, like for a bagged truck that is in the weeds one minute and then driving around the next, you may wanna consider that. the bolt in option works well if you don't weld or don't wanna pay a certified welder so it is legit for insurance or whatever, and you can always be welded in once you get it all done and decide you like it, wanna keep it but want to have it solidly mounted.
as mentioned in a previous post, sometimes a kit that is upgraded for what you want costs as much as a better kit. you wanna check the quality of the parts and how things like ball joint seal boots are installed, some are a sealed unit with the boot being pressed onto/into the joint and some have a floppy push on seal that doesn't fit well when the suspension is sitting level let alone when it is moving through a suspension cycle. I have done a kit that shipped with bargoon basement components and there would be no way the seals/boots would hold out any road dirt so they would soon need replacement. try to get a list of what the parts came from as well so you know what to look for in a few years when stuff may need replacing. also check the material thickness on the cross member and the wall thickness on the control arms. what size of brake rotors, what type of brake pad material, etc etc. sometimes the cheaper kit simply means you will get el cheapo deluxe components that you will wanna upgrade.
whatever your final decision is, you will need to also know the rake angle you want the truck to sit at when done and then set it up for that when you do your cross member install. otherwise you run the chance of poor handling and inability to set the wheel alignment correct. I really suggest you go to the heidts catalogue and look in the tech section for an article on "understanding independent front suspension". it will give you some insight on what to do and what not to do when you come to welding or bolting in the cross member. when done, at ride height od suspension, the lower control arms should be level both side to side and fore to aft. since the pivot for these is possibly not true with the steel on the cross member it is best to use the control arm pivot bolts as extensions of the pivot when setting up. you can push the bolts into their bores but bring them out in front of the cross member far enough to set a level on them to check side to side and fore to aft level of the actual pivot shaft. I suggest to use a short digital level sitting on a longer straight edge like a 4 ft level. you will need a long straight edge to level the frame anyway, which should also be done with a digital level. same for the fore to aft levelling. set the frame up on stands and secure it so you can do some heavy work with it and it won't move. recheck the level every once in awhile when working. if doing the bolt in cross member I suggest to use a reamer drill as they just require a pilot hole so they can get started and they leave a perfectly round hole of the correct size. regular drills tend to drill out of round or oval the hole.
do you have a plan for the build? lowered but not bagged?
https://www.homedepot.com/p/Digi-Pas...0Pro/305084719
https://www.homedepot.com/p/Drill-Am...S3-4/307840586