Never had to deal with Roland support, but both Alesis and Korg have treated me excellent over the years. One fella at Korg even set me an entire set of manuals free, for a keyboard I bought second hand.
I too have had good experiences with Roland Tech Support. My JV-1080 went down and I took it to a local Roland authorized repair center. The tech tore into it for about three days and finally admitted that he couldn't repair it. I asked if he had contacted Roland and the guy rolled his eyes, picked up the phone and half-heartedly dialed Roland Tech Support. Boy was he surprised when Roland picked up on the third ring. The Roland Tech told the guy to ship the module directly to Roland and recommended that the place not charge me for the time they had into it. I received my module two weeks later in perfect working condition and at no cost to me.