Esc's govern speed so yes the KK will work with 2600kv motors. The board is 5v so no direct connection to lipo.
I run the emax RS2205 on 2 of mine, using littlebee 20amp & pocket rocket 20amp.
Most esc's are decent now my pocket rocket where £6.75p each. & 2years old multiple crashes. Still going. Same with the littlebee. I may build half a dozen a year or repair for people. Except for a few I mainly use the pocket rocket just for a cheap build. I can honestly say in about 60 esc's about 8 died & 2 to unknown causes. I've killed 3 in 2yesrs on 3 quads.
Which I think is excellent. I got about 20 of them in a draw. The littlebee I bought 5 of & I still got the spare. I'm not 100% but I'm sure the pocket rocket are a re brand or clone of the spedix esc. Which also have good reviews. They look the same but can't really count the fets going by pictures. So for me if it works, use it.
If your a nut who wants a match then try the emax bullet. First build stick to 3S&4S
Not worth getting 3-6S as you probably won't have them long if you buy a 5-6S lipo.
Whatever you buy, buy spares, crud happens but it saves time.
Back in the days of having only one quad I took a week off work to go flying only to crash on day 1, I wasted a whole week because I didn't have a spare esc.
These where simonk with no blheli.
Never again I said. But a few months later I took my last 2 weeks holiday & they where wasted again. The quad was flipping so that problem is easy to sort out. If it is flipping because of the normal suspects. But the thing that sorted it out after 2 weeks of tinkering was a board reset. All because of a minor crash.
This was a naze32 by the way.
Never had such problems with F3 & F4 chips. Which brings me to your choice of board. I would suggest a better board for acro, if that's what I think you want.
OK use it but as soon as it packs in, atleast buy an F3 with the 6000 gyro.