I don't own a dingwall but I am looking at buying one, the fanned frets really caught my eye but for those that switched from a bass without fanned frets to the dingwall how hard was it to adjust to the fanned frets?
There's a lot of info and commentary on this subject both here and at the Dingwall site, but as a newbie to the Dingwall experience, I will share.
How hard is it? Well I will give you a very clear answer: It depends.
Over the past several years I have spent a lot of effort in developing decent left-hand technique. I try really hard watch my wrist alignment and keep my thumb in correct position. I TRY to stay consistent with my fingerings and had some method and approach to my playing. So, for me I really didn't think the fanned frets were that big of a deal at all. In fact, when you are actually wearing the bass, they don't even look as odd as they do when looking at it on someone else or in a photo.
When actually playing, the fret spacing the frets 1-5 area is wide enough that you can pretty much use the same approach as a parallel fretted bass, and there is enough room that there are no issues. The only variance I noticed is that it can be a bit of a stretch down to the C on the B string. (With the SJ basses, it is probably less an issue because it's A 35" B verses a 37" on the rest of the Dingwall line.)
From frets 6-12, it is not really an issue because that's the area where the frets are most parallel. I haven't confirmed it, but I assume that there is one perpendicular fret somewhere on a Dingwall. To my eye, is seems to be seven or eight.
Above the 12th, is gets a bit touchy for a couple of reasons. One is that the fanning becomes more pronounced and, obviously, the frets are closer together. Further, I think that for most of us, above the 12th is where we tend to use our eyes on the fb more, and I agree with Sheldon D. that the fanned fret concern is more visual that anything. Although, there is some logic that that suggests the bass is more comfortable even in the higher resisters. I am one of those people whose pinky is significantly shorter than my ring finger. For me, my fingers tend to natural fall in the right places on the fanned fingerboard more so than with a conventional fb.
If you are interested in a Dingwall, I would not let the fanned frets be of concern. It is pretty easily argued that the benefits FAR outweigh any concerns. Once you hear the clarity and articulation of notes on the B and E strings, you'll figure out the fanned frets. No matter how you think it is, it's worth it!