Maybe it's just what I'm used to, but doing anything other than calculating the value of an expression with RPN seems hard to me.

    (x-3)(x+2)-8 > 2x^2+3
    x^2-x-8 > 2x^2+3
    x^2+x+8 < -3
    x^2+x+11 < 0

vs

    x 3 - x 2 + * 8 - x x * 2 * 3 + >

how would I simplify the expressions here? Maybe it's possible without transforming to infix but I can't do it.