Pat,
My post was because you used the word "best", and when someone uses "best" instead of 'one way', that is usually their chosen wording because "best" means "best".
That said, and not to dwell on it any longer, the 2006 IRC states: (underlining is mine)
- SECTION P2605
- - SUPPORT
- - - P2605.1 General. Piping shall be supported in accordance with the following:
- - - - 1. Piping shall be supported to ensure alignment and prevent sagging, and allow movement associated with the expansion and contraction of the piping system.
- - - - 2. Piping in the ground shall be laid on a firm bed for its entire length, except where support is otherwise provided.
- - - - 3. Hangers and anchors shall be of sufficient strength to maintain their proportional share of the weight of pipe and contents and of sufficient width to prevent distortion to the pipe. Hangers and strapping shall be of approved material that will not promote galvanic action. Rigid support sway bracing shall be provided at changes in direction greater than 45 degrees (0.79 rad) for pipe sizes 4 inches (102 mm) and larger.
- - - - 4. Piping shall be supported at distances not to exceed those indicated in Table P2605.1.
I know 'logic' says you can use whatever you want, just slip some protection in there, however, we have all seen (I am sure) where that 'slipped in protection' was insufficient, moved out of place, etc., leaving *no protection*.
So, "logic" says the code says what it does for a reason, and that reason is what I just described above - to prevent galvanic action between dissimilar metals.
Thus, not only is "the best" answer, but "the real" answer, is to use compatible metals.