I have the grapple on my 50hp and while I don't use it a lot, when I use it, it is one of the best attachments I ever bought. If it was not for the larger one I would have ordered one for the BX by now. Heck I have even thought about getting one for the BX just for working in the tighter areas - love that machine!
My LandPride Operators Manual says the SGGC0548 weighs 158 lbs. I do not know the actual weight of the BX bucket but I don't think there is a huge difference as I have about the same difficulty moving them around my shop floor (have not made carts yet). My guess is the bucket is a little heavier. The QA is maybe 50 lbs but that is a total guess on my part. I can pick up enough with either implement to up my pucker factor enough to make sure I keep the loader arms close to the ground. The increase of the pin distance with QA on has not been noticeable to me. I did use the grapple in direct pin mode before I got the QA. Again, no big difference. Sorry I do not have all exact numbers for you, but will conclude saying that there is no way I will ever be without that grapple. It's been a tremendous addition to me.