Hi Dave-
I can highly recommend the Dynavector, if the Rega phono stage can handle its low output. The 17D2 is extremely dynamic, rhythmic, detailed, and non-fatiguing. I think the Goldring sounds quite a bit "muddy" and non-dynamic compared to the Dynavector, especially in the low end. Wait 'till you hear a slap bass with the 17D2. You'll love it! I haven't heard the Koetsu, but I'd like to someday. A lot of AudiogoN members seem to really like them. Maybe next time. :-)
Good Luck,
Ed