Looking to improve my skill set and move into using a flash with my Nikon D7100. Obviously, the builtin flash on this camera does not really do much for you, especially in outdoor situations. So I have begun to look into flashes to use that would suffice in both on and off camera situations. I would prefer one that had radio transmit ability as line of sight does not alway sallow for best of circumstances. I am probably leaning more towards aftermarket flashes than OEM due to costs (although I have considered used Nikon SB 700 and 800). so, to those with significantly more knowledge and skill than me, what would be a good 3rd party alternative that allows for radio transmit, good GN, good to better construction, and most importantly - reliability? I have looked at and read reviews on Yongnou, Godox / Flashpoint, Altura, etc., etc. After a while, my brain goes to mush and no longer does this make sense. Additionally, if I am not going to be using a flash a lot, does it make sense to stay with AA battery use rather than Li-Ion? From what I a=have seen, looking at Amazon, cost difference on 3rd party units is about $60 - 70 USD. Warranty also seems to be across the board - anywhere from it ends when you get it to maybe a year, if buying from Adorama or OEM. Thanks for any advice offered.