Speaking as someone who has a terminal diagnosis, and who isn't feeling all that great right now, this issue isn't just a matter of academic interest - if this legislation passes then it will, for me, become a very real option.
What I would say, alongside all the talk of safeguards, restrictions and freedom of choice (which possibly implies a degree of cut & dried fictitious precision) is that the reality of living with a terminal condition and considering what the personal and family implications might be at the point my health significantly declines to the extent that I'd consider arranging for my death - is that things are likely to be messy and imprecise and I'm not certain that legislation, by its very nature, can effectively deal with the subtleties of the messy and imprecise.
What legislative caveats can there possibly be that could deal effectively with the likes of: pain, fear, uncertainty, individual personalities, the prospect of forthcoming grief, regret, feelings of hopelessness etc etc etc - and all mixed up on a case-by-case basis? I can't see how variation of issues like these can ever be legislated for in a way where the solution (the legislation) doesn't become a bigger issue than the problem (that some people may wish to end their suffering and shorten the process of their death)
For myself, provided I have capacity at the point I elect to schedule my death, I'd settle for a simple removal of the threat of legal action against friends and family or professionals should I ever wish to end my life and that I could access professionals who felt able to arrange for my death to happen at a time of my choosing - just as I could, in the event of a my having a future medical emergency, elect for 'Do Not Resuscitate'.