(on edit: OP, I saw you mentioned off-road... Mevotech makes a 'TTX' line (green boot) that seems to be popular; I think some of the ORTB guys have them (as another brand, but they're the Mevotechs), and have posted about them on their forum. Might be more 'off-road' than you need, but I'd rather have 'too much' vs. 'fail', myself)
I tend to go with the Moog 'problem solver' line (the K6663 / K6664 fall in this line), for two reasons:
- The 'problem solver' part is that the ball shaft is limited in travel to one axis - inward / outward (they require installation with a reference mark on the ball joint aligned in the proper area on the arm.) They also have a pretty beefy shaft / ball, especially as compared to OEM.
- If one ever fails, I can go to any retail store that carries them and get a replacement (they're readily available at several different chains). The cheapest place to get them is Rock, btw (and I wouldn't hesitate to return them to a retail store I didn't buy them from; they get reimbursed by Moog, since the product has a lifetime warranty.) Note that the AC Delco 'professional' line is also warranted for life, but fewer retail shops carry them; some that do are by special (whse) order (most people don't spend the extra for the 'pro' lines, so the retail stores tend to stock only the 'advantage' line (which is NOT warranted for life).
(a third minor reason is that the Moogs have a relief outlet in the boot; should you get overzealous with the grease gun, you won't blow the boot (I've done this with other brands). The boot also seems to be (semi-)resistant to careless / rough treatment during press-in (I've done this, too, with other brands))
Does that mean that everyone that has complained their Moog products failed was mistaken? Nope. Not by a long shot. They're 'not what they used to be', as well as no longer made in N. American plants. But for the difference in price, as well as their ready availability, I'm still willing to take a chance with them, at this point.
Note that this only applies to Moog ball joints. For other suspension pieces, I'm not captive to that brand, and will buy others, depending on price / warranty / performance / difficulty to replace (again).
And it goes without saying... if you don't keep them lubed, they'll still fail (once a year is generally sufficient, unless you're doing hotshotting)