We live in a sandfly area and only use a mixture of Dettol and Olive Oil or whatever oil you have in the kitchen eg grapeseed. 50-50 strength and I put it in a plastic spray bottle of the likes that you buy from The Plastic Box. As someone else said you need to shake it and remix each time before using. You smell clean! Even the monster sandflies from Karamea stay away from this. If you do get bitten anytime dab lavender oil on and you won't suffer the bite.
Bushman is tops took 2 cans to India and nothing came near me, the bugs over there are so big they knock on you door to be let into your room .It even stayed on with water pouring out of my skin, cool days were 36 deg.Being a spray can its quick and easy to put on .
Update from the coast! I'm in Haast and am using the trusty dettol/baby oil mixture and it seems to be working a treat. Pulled into Ship Creek to do a couple of walks around lunchtime and swarms of the beasties descended on me, being fragrant and all. Applied plenty of the brew and while the buggers stayed put they didn't bite so win!
In further news it is no longer possible to get a feed at Lake Paringa.
Tour is going fantastically, will have a couple of epic blog posts up sometime next week. The big climb to the Haast Pass is tomorrow. Yay! Shockingly I'm loving the climbing! Who'da thunk!!!