Depending on your weight (70 to 80kg) but in 18 to 25 knots a 9 meter bow of any brand is probably suitable. I ride a 122 board in those conditions with a 9m switchblade - best fun ever!
Bar pressures seem irrelevant really on 9 meter bows due to the fact they spin in their turns and more so in the winds you like most to kite in. Also own 12m (Switchblade) and 16m (Assault) bows and yeah it can be a different story especially when in surf in lighter winds. If a 12 meter bow is more your size then maybe forget the bow and go for a vegas or simmilar c kite - good depower, more wind range than old c kites safe fifth line and so on and so forth

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If bows are your thing and seem so from your general laid out question look more at the quality, the extra little things or the price factor. Yeah ok i have just stated the bleedingly obvious.

Personally I like the bows that arnt too flat profiled i.e. switchblade over the crossbow or lf assault. I looked into a halo but to me the bungee thing on the bar looked too gimmicky and thought the leading edge looked rather impregnated.I guess (ironically for me) it was done to reduce inversions and bar pressure issues. As some mentioned the sonics seem not so flat and have had good reviews, maybe an 8m would give you what you want. Then again comments on the new 07 switchblade seem good as well with regards to low bar pressure and lack of bar pullies - Best of luck choosing