big bike for a tall person

Privateirony

i am having issues with my current bike as i feel somewhat cramped and uncomfortable on it. I am 6' 4", so rather tall and am looking for a good LARGE hard tail for approx £800, i have started looking at 29ers but am unsure if this is the right road to go down, any advice is welcome.

bikes looked at so far:
CANNONDALE Trail SL 29'er 3

(this is not for me btw this is on behalf of a friend)

.blitz

Would not get too hung up on having a 'big' MTB tbh. A bike shop may try to convince you that you need something stable like an oil tanker that fits you like a road bike and is ideal for pedalling efficiency but as your confidence grows you will need room to move around and being stretched out over the top tube with your legs at full extension is not a good position to be in.

Try as many bikes for size as you can when in the attack position and take it from there.

lostboysaint

I'm 6'4" and it's just a case of looking around and trying a few.

Currently riding a Transition Bandit XL (90mm stem) and an On One Inbred (26) 20" (90mm stem and long seat post).