Is this complex idea worth pursuing?

Hello fellow hackers.

I've been puzzling with an idea for the past week or so, and I don't know if it's worth pursuing to develop an "MVP".

And in most cases I would just do it, but with this one I am doubt for two reasons:

I won't be able to turn out an MVP super quick as the idea involves a high level of encryption and security. With my current bandwith (not a lot), I would probably be able to turn out an MVP in a couple of months.
There is one large competitor (VC backed and hiring like crazy) doing more or less what I want to do. And I won't be able to do it much cheaper than they do, and probably not much better either.

Looking forward for some feedback (although I could imagine what it would be after actually typing this out loud) 🙈