Does anyone have bad experience upgrading SXT which currently has v6.3x to the latest version? im asking because i have to do remotely. Any suggestion are welcome.

Most probably you will be ok. However i don't know your configuration and what might go worng.

The configuration is pretty simple. Just wireless configuration and bridge ports.
I had upgraded MT at home, and adter upgrade it didnt start up, i had to unplug /plug to porew point,after that evrything was okey.
That why im asking for.

No one can tell you for sure if something might go wrong or not.

actually my question is should i upgrade step by step up to the latest version or directly to it.

actually my question is should i upgrade step by step up to the latest version or directly to it.

Personally i either upgrade or not upgrade my device.. Never done a "step by step" upgrade.

I'd do in at least several step, making sure none of the steps introduces more than one major change like wireless packages consolidation, master-port removal, etc.

There Are some Wireless changes After 6.41!
Country Settings, Channel usage is more strict and
New options like Outdoor/ indoor could make Problem