What router did TM give you? If current model, should be ok for 800Mbps on LAN. Wifi, likely your device is the bottleneck.

do you really need tri-band? 

if no  better get ac88u  (dual band)  cheaper

unless you really need tri-band.  only you go get ac5300.

dual band  = 2.4ghz + 5.0 ghz  (have 2 wifi band)

tri-band = 2.4ghz + 5.0 ghz-1  + 5.0 ghz-2  (have 3 wifi band)

for asus ac88u  = 2.4ghz + 5.0 ghz  (1000mbps + 2100mbps)

for asus ac5300 = 2.4ghz + 5.0 ghz-1  + 5.0 ghz-2  (1000mbps + 2100mbps + 2100mbps)

I'm also targeting on this router. Been reading reviews and good feedback, I don't think one can go wrong this router.

i just got my ac88u today  going to try it after work.
basically the specs and performance of 5300 is same as ac88u  since they have the same hardware. 

just that 5300  has tri-band.

if you have alot of cash to burn.  then can get 5300. 

but for my uses.  i dont need tri-band.  coz i dont stream 4k videos to TV or play ps4.   

for those entertainment usage  i will use LAN connection.

my main purpose of getting good router after unifi turbo upgrade is have the wifi performance.

Yeah, I quote one review below for you. Worth the price