I owned a 400 WRM for 4ish years. Didn't really like it.
Kinda of a dead tone, even with new strings. Had weird harmonics north of the 12th fret on any string. Had repeated issues with neck warp...original neck started to twist along its axis, Ibanez replaced. Couple months later, same thing...Ibanez replaced it again. A couple months later, warranty expires, and the third neck ended up getting snakey and wierd. Ibanez wouldn't help me.
I dealt with it like that for 3 years. Pissed me off righteously, but I could make it playable by loosening the truss rod and accepting a high action.
A few years in, my preamp got fuzzy...mids cut in and out.
Aside from these issues and it's general flabby tone, I also hated the finish. Looked awesome, trans red over quilted maple...but it was thick. Like a plate of glass over the wood. I always felt like I was playing plastic.
BUT...I liked the scale, width, thickness and flatness of the neck. Even with my bad neck, it was an easy player. I look forward to another 35" scale bass someday.
Obviously, I got a bum bass. These are generally well liked, here and out in the world at large. But be aware, especially if your buying used, there are lemons out there.