Hi, I own the X1 HD & the SD1, and I have played the PA80 and I think is a VERY,VERY, nice keyboard, the feel/touch of the keys (to my taste), I rank them like (from great to ok):
1.- SD1
2.- PA80
3.- X1
in sound, between the PA & X1, is close, but the X1 has the edge....even is a two years old.....of course, the SD1 has the lead, like I said, is to my taste/needs/etc. Well, like everything else, there are other items to consider, if you like/feel is "friendly" to operate, one of the most overlook things to consider is the factory/dealer "SUPPORT", besides service for repairs, etc.....I recomend you to play both, after all, you are the one is going to use it....hope it helps.
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mdorantes
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mdorantes