Okey-dokey, I got myself into this, and have no one but myself to blame. Now I'm just trying to escape with my life—people are passionate about their ballheads, I'm finding. (Hey, keep yer jokes to yerself!)
Another lightweight but strong ballhead with fanatical adherents is the European-designed, Korean-made $340 Markins M10 sold by Nikonians. It's the heaviest of the four I've discussed here (I include the RRS BH-40), but is roughly comparable weight-wise to all but the much lighter RRS BH-25.
Again, this is one I haven't used or seen, which begins to beg the question, why am I writing about ballheads? My question exactly. Here's how the race is shaping up so far: RRS BH-25 for the ultimate in light weight, small cameras, backpacking; Acratech for work at the beach or other messy environments (it can be dismantled and cleaned) and as an all-purpose lightweight head for heavier gear, albeit with different movement limitations than Arca-style ballheads; and the RRS BH-40 or Markins M10 for decently lightweight versions of the Arca type.
Issues in choosing: lockdown strength; lugging weight; cost; "captive" knobs/levers (i.e., that don't completely unscrew and come off, and thus can't be lost); position of controls; control pressure required; panning base, yes or no; damping and "flopping"; service and warrantee issues (this seems to be a strength across the board).
Hope these entries are providing leads for you. Sorry I'm not more of an expert. Tomorrow: your humble writer takes it on the schnozz from fans of other ballheads.
Posted by: MIKE JOHNSTON