From the hardware point of view, the PTCL/Tenda W150D is not much different from other BCM6328 based routers but the difference surely lies in the software/firmware ... so let's take a look at the gui side of things ...
From the start it was apparent that the firmware for PTCL was not 'special/locked' one and just used image replacement replacing Tenda's images/logos with those for PTCL ... anyways it also didn't seem to work well, felt kind of like a beta version of the firmware ... couldn't hold onto some settings ... my long line and difficult stats didn't help either (awaiting conversion from copper to fiber) ...
so in desperation I looked at firmware updates for the router on Tenda's website knowing full well that a corrupted/interrupted/slightly-changed firmware update would brick the router with no obvious way to recover as serial & jTAG pinouts are not known (there are some test points ... but lack of interest) and no full flash backup currently ... I decided upon v1.0.1 of the update (taking note of the version previously installed ... http://www.tenda.cn/tendacn/product/show.aspx?productid=389&type=2) and flashed the newer firmware "bcmw150dv3_fs_kernel-IPOA" ... it was successful :) and now its running Tenda's original firmware ... and things have improved significantly! Be sure to clear browser cache as well!
Update: The board seems to originate from Micronet Taiwan with the product number SP3367NL! I had to remove a little of the header to install Micronet's firmware on the router (I was upgrading from Tenda's firmware mentioned above)! The modified version is here: http://sdrv.ms/12HdFOr and the original product page is at: http://www.micronet.com.tw/mod/product/index.php?REQUEST_ID=cGFnZT1kZXRhaWwmUElEPTEwNQ==
Caution: If you follow with a firmware update, you alone are responsible for your actions as a firmware update can brick your router and may void your warranty!!!
(My upgrade path: PTCL's firmware->Tenda's Firmware->Micronet's Firmware)
In my haste, I forgot to take screenshots of PTCL's firmware but one thing for that firmware I know is that the telnet username: admin and the password: admin ... if you want to play with the commandline ... you have to type "sh" without quotes to get into the busybox shell!!!
Here's Tenda's interface (almost same as the old one):
Any benefits??? Yes, the firmware keeps settings and seems to work much better than before ... though it runs very hot as usual and I have had to 'enlarge' some openings making air flow better ... another thing (more related to line quality than router) is that although it can hold onto dying connections well, it holds on too tighly showing connectivity via leds but you cannot use the internet until finally the connection dies and the router reinitiates sync after quite sometime ... so for noisy lines, you may have to wait a while before reconnecting (hoping shifting to fiber would sort this problem out at its roots)
Next time, we'll take a look at Telnet and some tweaking options provided by the root access ... in case you are wondering, the username: root and password: ConsoleFireitup (case-sensitive) ...