If its the right price go for the 650sx, ive had sitdown skis for 10 years now and only just took the move to standup, my 650sx ows me £300 uk pounds including the trailer, it took a little cleaning but thats it, but it has been a lot of fun over the first few rides this year, and has paid for it self in fun alone, i am lerning alot with this ski and i will move on to a SJ,
i always wonted to try standup but didnt wont to invest to much £££££ incase i hated it, turns out i love it, but the cheap 650sx has allowed me to get in to standup at the right money and at the momment out performs me,
I hear what people are telling you and sort of agree, but if the sx is cheap you will have you moneys worth in fun, then enable your self to get past the learning and like me get a SJ next year when you know you aint going to be waisting the money,
Mick