Yes, that's where you go to access the play hole (but I would recommend just doing a Middle-Lower Tenmile run with a play-break there). It's hard to have a good feel for when the feature is good but between my experiences and talking with Matti, here's what we think the current situation is:
Low Side of In-350
Low Side of Quality-400
High Side of Quality-600
High Side of In-650
When I was there at 650 it was good (spin, wheel, maybe loop, maybe blunt) but was flushy. Eddy access was good. At 750, it was more of a stomping wave-hole and was definitely better but catching the eddy in time to get back up was tough. It sounds like the feature is similar quality from 400-650, just more retentive on the lower end of that spectrum.
"The world would be a better place if everyone kayaked."-Brad Ludden (Valhalla)
"You only get one chance to run a drop blind."-DD