I have been riding new Slashes for the last week and bought a 9m and 7m with a plan to get a 5m at a later date - so I'll give you my first impressions frmo 2 sessions on each kite - Basically I think they are awesome and don't really have anything negative to say yet
I am a fairly experienced strapless wave rider, weigh 95kg and was riding a Firewire Evo 5'3 for every session. I pay full price for my kites and have no brand affiliation. My older kites are Naish Parks (2014) with which I have been really pleased so I guess I do have a little bit of brand loyalty.
First up build quality is exceptional. The quad tex is ultra stiff and crispy (to the point where its difficult to roll the kite up) and gives the kite a very solid feeling in the air.
In the air the kites are fast and pivotal in the turn and have a very fast and direct steering feel. Low end is excellent (not quite as much as a Neo) as you can see from the first graph I was comfortable staying upwind in 14-16 knots on the 9m. On the waves the drift was excellent and when I did manage to finally drop it while surfing a wave I could relaunch before the next wave of the set even in light winds and with a sweep - I think the speed of relaunch is helped significantly by how structurally solid the Quad tex and the reinforcements make these kites as they just hold their shape so well. I'm yet to explore the high end
The 7m is so much fun and performs great as a wave kite - again very fast, direct feeling and excellent drift. I feels really good from 17 - 22 knots and am yet to really push the high end again on this one
The range of these kites seems to be so good that a 3m size difference would be reasonable (although I like riding as small a kite as possible) I'm excited to see how the 5m goes when i save up the money to buy it .