Hitman....

With only two challenges remaining in Professional Sapienza I've reached enough of a mastery level to unlock the Antique Emetic Syringe.

Like Paris on Pro mode and the rest of the game on Normal, once you get used to the changes and additions in security/camera's you start to get comfortable. Being comfortable in a level lets you push the limits further. Having the one save point is still tactical as well as practical. You need that save point when you reach certain plot/assassination arc's that can go multiple way's. Tactical time saver. The one real pain in the mission is that you still need to destroy the virus. Thankfully you can get lazy and shoot it with the silverballer from across the cavern then make a run for the seaplane. Not very Pro but my time is valuable ;-p

Only two more challenges to complete the lot. 'Weeding the garden' is simple enough but the Sniper Assassin challenge is proving a pain. I seem to be spotted no matter how hidden I think I am.
I got the original normal mode sniper assassin by subduing both targets, grabbing a smuggled sniper rifle and shooting them from point blank(poison him with the food, poison her with the drink. subdue both and drag them to her main room, recover the rifle and shoot). The things you end up doing to make it work..... I might have to try the same for the Pro sniper. Unfortunately for me a large sniper rifle is a noticeable item on Pro mode. All part of the challenge work-through. Timing and location, location, location.