Hello rosnik, thanks for comment.
Do I understand correctly -that you want to use an <span style="font-size: small">18x6 prop </span>(i.e. APC Sport) on the 2nd Angel ?Please confirm.
I very certainly have a few suggestions for motors, that are MUCHMUCH cheaper than Hacker A50 S motors.

<span style="font-size: small">In the UK, theHacker A50-16Lcosts &pound;141.69(english pounds)(=</span><u><span style="font-size: medium">$215.06</span></u><span style="font-size: medium"></span>converted) -from WestLondon Models.
<span style="font-size: small">-Same Hacker motor in USA is only $149.99 (less than 70% of UK price).
<span style="font-size: x-small">
<span style="font-size: x-small">In the UK, the Hacker A50-16S costs &pound;114.69 (english pounds) (=<u>$174.20</u>converted) -from West London Models.
-Same Hacker motor in USA is only $129.99 (73% of UK price).
</span> -Itmust bevery irritating for people in UK...</span>
</span>
PS: I also have an Angel50, and in this plane I use a PJS 3D 3000 motor (I have had this for 12 years ...!)
-motor is 345g, Kv 490 -see http://www.pjs.cz/&amp; http://www.pjs.cz/product_info.php?c...products_id=45
The motor still works great ..! -I also use 5S LiPo, no need for 6S with this motor.
With a 16x10 prop, and 5S LiPo, I get a reading of 1550 W (current &gt;85A ...!). That is a lot of power for this2.7 kg plane ...

<span style="font-size: small">PPS:I can suggest several motors that are ~30% of Hacker motor price .. -Once we know more what you want.</span>