Manfrotto makes good stuff. I've used their stands and adjustable poles. I've not used the bar heathen linked, but it is well regarded by other tapers running multiple mics, because it is sturdy, stable and easy to use. One potential issue is that as aaronji notes it is quite large, perhaps as much in appearance as in actuality. I've not seen any one do this with it, but as a way of minimizing overall visual impact I'd be tempted to rotate the rather tall movable mic attachment "risers" forward instead of having them point upwards, assuming the bar is round in cross section and that's a viable option. Doing that would place the mics, bar and support risers more or less in the horizontal plane and greatly reduce the apparent visual size of the entire array, especially for anyone behind the recording position.
It is helpful to have a few alternative mounting options to choose from, and you are likely to home-in on which work best for you after going through the motions and feeling out what you are comfortable with at a few shows. May take some trial and error there.
Here's another general rule of thumb setup suggestion- when using omnis or forward-facing subcardioids as the outside pair, try to arrange things so you can get 3' spacing between them. 5' is better, even 6' or more if possible. The problem is that represents a lot of spacing given what is available from most mic bars and often is simply not practical unless using more than one stand. If you are using directional mics as the outside pair you can do the angle/spacing trade-off thing to get away with less spacing by angling them outwards, but its better if you can achieve enough spacing to not be forced into doing that. Some setup details can help, like attaching the outside pair to the outer ends of the mic-bar such that the clips and/or shock mounts extend beyond the overall length of the bar, increasing the overall spacing. Such an arrangement also helps minimize visual profile.
One way of achieving that spacing more easily is using a lighter-weight pair of mics for the outer pair which require less substantial support. One way of achieving that may be simply placing the heavier pair of mics in the center, another is using arrangements which separate the the mic capsules from their amplifier bodies with a cable, so that only the capsules need be supported out there. I use miniature DPA omnis on thin telescopic arms the diameter of a pencil which I can extend out to 6' and are nearly invisible, with larger/heavier mics in the middle where they are easily supported.
Using cardioids, I'd try to arrange things to get 2' at minimum between the outside mics, and if you can get 3' or even more all the better.