I have Spec-R blades on order
. But it's a good thing that Serpent includes extra blades with the original kit.
Over here guys mostly run 416/417. The Tamiya arms are a lot harder. Will have to test hard serpent arms next, I ordered the hard C-Hubs (normal wasn't in stock).
OVA: I did put shims on top of the steering columns and that got rid of the slop. For the bridge with the smaller bearings I tried various shims below the bearing (per manual) and on top of the bearing, sandwitched between the screw. Still wobbly. However I still get tons of steering and the snake does love to hug the corners, so it's not a huge concern at this time. I just hate slop.