Hi, I've got TP-LINK TL-WR841N v8.4 with lastest TP-LINK firmware. 
My questions are: 
1. When I update the firmware what is a change to delete U-boot from chip? Is it safe to update if I have serial console ? 
2. Does dd-wrt and any firmware like openwrt/tomato/gargoyle "touch" the bootloader and if something goes wrong I can always recover device with serial console or there are some doors to loose my bootloader? 

Which version of openwrt is the best for v8.4 and have working client mode ?

Thanks and sorry for my bad english

your uboot is safe unless you do some tp-link upgrade, that usually updates also uboot -.-

version.. trunk works better but can have bugs, AA has bugs for sure ( wifi not stable 100% ) but it's safer if you do not have serial...

I have serial so I am master and may fix any wrong custom firmware update failed ?

yes

Great! I have another question: Is it possible to amage art partition and how ?

you can damage uboot and art by typing random addresses in erase command from uboot prompt, but you can't from openwrt since it has write protection on those partitions.

Thanks nebbia88 for your answers !

When I use client mode which mac address uses my router(WAN, LAN, wireless) to connect to another router. Which mac address is shown in main router ?
Is luci integrated in firmware for my router and which version have it ?
How about macc address - are they the same ? Is it possible to change (WAN, wireless) mac addresses ?
How about wireless speed is 300mpbs reached ?

(Last edited by Experimentator on 13 Apr 2014, 20:51)