Here's my $0.02 worth... both are great knives.
Jon has the Ginga line made for his shop, to his specs.
Jon has also been a big fan of Suisin, using them himself when he worked the line. He is personally familiar witht he makers and has a lot of respect for them. Suisin does use a stainless, for both single and double bevel knives, and in that respect they are a bit different than other "traditional" makers. They recomend using a micro bevel with their steel and the way they produce it. SS in single bevel knives is very untraditional.
Suisin also recently had a fairly big price increase, as have many other makers. Jon is very particular about the makers he sells, so if he sells it, it's going to be good. Saying that, there are other sellers as well that deal wth Suisin, so I'm not just blatantly plugging Jon.
Apart from the steel in the Suisin, both knives are going to be very similar. Probably only an expereinced and very particular knife geek is going to be able to discern and develop a preference for one steel over the other.
Shibui - simplicity devoid of unnecessary elements
Just to clarify, Suisin produces plenty of single bevel carbon...
Everywhere you go, there you are.
I really like both lines of knives. Between the stainless, I prefer Ashi for overall sharpness and toughness but if you're gentle, the Suisin seems to hold an edge longer, esp. once I took Jon's advice and put a microbevel on it. The fit and finish is similar and I will second the nice, large handles on the Suisin. In terms of value, I would personally go with the Ashi, esp since the price hike.
Did anyone end up getting Jons thoughts on this?