Im going to get a BT open reach modem (i was offered one, they may be along after i post this). Do i need a specific model ?
Are there any other models of modems that work and can be unlocked, do some work better than others, for example, i read that the netgear DM 200 is a more current modem and would get slightly faster speeds.
Im not adverse to reprogramming them and i am a seasoned SMD and BGA IC reworker if any need this kind of work.
Many options have been discussed many times on these pages before, there are many opinions and many choices. Try the search function, or something called Google.
This shows the advantage of having an FAQ where we can review what router works with TalkTalk and how to set them up. If there is one, could you link to it please? If not, could this be done?
There is a help article about third-party device settings, yes:
Any router/modem which advertises itself as compliant with Openreach systems should work. The ease or difficulty of setting it up with a TalkTalk connection is likely to be down to how good/poor the connection wizards/GUI on the device are.
Who would provide such a list? I have already told you to look for compatibility assurances. The one you mentioned earlier i.e. the Netgear will work according to their website. Which is where I would expect to find such information.