The SSV wheel (I believe) is the same as the HBD wheel option. Fairly similar design to the HSV (flat base, bolstered grips) but the HSV wheels is thicker again, with perforated leather.
The HBD wheel is much nicer than the SS wheel (which I've seen with red inserts as well - looks really silly on the big, round, skinny wheel) - but the HSV wheel is just that next step up again. You can often pick up the HSV wheels as surplus. Looking at the link I posted again... I think that may actually be the HBD wheel as well (someone on here was caught out like that before, also - it's hard to tell from the pics) - the difference is visually quite subtle (It looks to me like the SSV wheel has changed between your one and what was around when I bought mine - Aug 08 - as I'm fairly sure the grips weren't bolstered then). I think the big difference is the leather used - the feel of the wheel is different.