I've been running various DX8 beta versions for a couple of months now. On my computer it works just fine. AH, WB, AW, FA, CFS2,GPL, SCGT etc all work with no more and no less trouble than they did before with DX7a. To see the benefits of it we'll probably have to wait until games/sims are coded to take advantage of it. If you're nervous wait until your latest game requires it before switching over.
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