The existence of Nessy is about as equal to Manipogo and the Mokele-mbembe, all three of which usually tend to have the same characteristics.
All of them tend to look like a long necked dinosaur of some sort, and prefer murky and damp environments (loch ness is extremely murky) or at least survives near a big body of water really - since Manipogo isn't set in a murky lake, but Lake Montoba which is a huge fishing area from what I understand.
Then again, that's not likely. I'm willing to bed I'd have a better chance of winning the lottery on a ticket I never bought, while getting bit by a shark in the middle of the Sahara, whilst whistling - which I've never been able to do. Oh, and then afterwards being struck by lightning three times in a row.
I'm sorry. Loch Ness isn't the mystery it was 30 years ago. We know it's depth, we know where many of the tunnels head off to - and for many where they simply end. The last big real "evidence" that seemed even remotely close to saying "Okay... maybe it's almost plausible" was a doctored photo from 2001 that wasn't even half as inviting as the infamous surgeon photo. This video being tagged as the finest piece of evidence is sadly true.
Because there is no other evidence, everything's been disproved or simply was too unreliable to even bother with outside of the weekly world news.
It would be cool, but just isn't there.