Thanks for all your thoughts, ideas and insights,
I'm a bit keen on these Makos now Eppo!
I'm punting I'd like a king but am interested in your thoughts. So at the risk of Paralysis by Analysis here goes...
I've riden the hammer 144x40 for 3 yrs and hammered it! It isn't broken at the moment but in spite of the old adage, it seems a good time to try another twin tip/ mutant to replace or provide a stable mate to the hammer. I think it would be especially good to be able to use the Mako in small sloppy cross onshore 15knot conditions which can be common here at times. Currently in these conditions I use a SB. The purpose of these sessions is just to get wet and have a bit of time to myself and practice strapless airs, tacks, kite tricks through transitions and piss about. Usually its worth it but staying up wind can be a drag especially if the tide is not assisting.
I like the sound of the mako because its very likely to be faster and more responsive / useful than the hammer in light wind. It would go up wind better than the hammer, its really versatile and still good for cracking big turns and will compliment my yogic seabird emulation program well. Big concaves are always fun. That its different is interesting itself.
Few others kite here so i've really limited access to different boards. I've riden a wainman Blunt 135 (big single concave) which was really fun and so light. It seemed much shorter than the hammer. Also a north Xride 136 which was fun too but not so locked in or good for carving. It was quicker, planed earlier and easy to ride. Ive also recently ridden a tricked out freestyle cabrinha - Blah!
Re: Give me your weight, kite sizes and wind ranges you rare talking about and the kite brand and type. Throw in the hammer as your benchmark and the other board you are using now.I'm up to 73kg dry
I have a full quiver of 1.0 wainman kites (except the big mumma) really I only use the 7 and 9m.
The biggest I use is the 9m smoke as I find the Boss (12m) is frustrating to keep up wind in light airs. My 9 is pretty tired now so I've just picked up a 10M Reo which seems to have much the same bottom end as the smoke. If i'm to get a bigger kite I might possibly consider a 10M switch blade..

I'm not keen on kites over 10m.
I use PU surfboards mostly;
6'2"x19.25"x2.5" fishy floater for lightest air (pretty pointless really),
6'0x19"x2.25" fine pocket rocket which surfs well up to 4',
a black epoxy wainman surf series 5'7"x17"?x1.75"?
I just came across a 5'7"x19.25"x2.25" rusty magic door with 3" of nose ground off which will possibly knock out the fishy floater.
There is probably only a couple of knots between each board given the same sea conditions so using the smoke without a bridle on 22m lines i'd use:
the floater from 12-17knots
the pocket rocket from 14-20knots
the wainman surf series from 16-25knots
The hammer only comes out when I'm air starved or the sea is pretty un-organised and messy. I suppose it starts at 15 -17 knots and is a big hoot at 22-25knots on the smoke.
I always kite at surf beaches or reefs with cross onshore wind 50% of the time, Onshore 30% and cross or cross off 20% of the time. Essentially the land here is too hilly and moist for great wind conditions.
So, should I go the king (165x44) or 150 (150x40)?
I can see my largest kite, being a 9 or 10m is a bit limiting in this scenario but i'm staying at or under 10m. The boss might possibly be better suited to this type of board but I'd be trying line extensions on the smoke or Reo first. I'll still have the hammer for windier conditions.
Is there really much difference between the earlier models and the 2013 with the tucked rails? speed, turn initiation / rail grab, pop...
Thank you for all your feedback and inspiration.
Pete