Cheap double glazing options: one month later

I've been trying three different double glazing options now for about a month. And we're now finally starting to get some cold weather (although we haven't had a lot of rain all year).

The "real" double glazed unit is working fine. On a very cold morning the is sometimes a bit of condensation on the room face of the window (the side you can touch when inside the room). I'm waiting for a nasty southernly with driving rain to see how well the way I've fitted it works, but from a insulation perspective it seems to work fine. The double glazed unit, from Ultra Glass cost $110 for a single 512mmx1250mm window.

The cheap acetate (plastic) extra layer seems to work just as well. But cost about $5. I've read that they last 1-2 years. Not sure what happens to them after that time. On a very cold morning there is sometimes a little condensation on the room face of the window (in side you can touch when inside the room). One of the sash windows also has condensation in betweeen the glass and acetate so I'm assuming there is a gap in the putty holding the glass in the frame. I plan to renovate this window and replace this glass with laminated glass sometime - I won't doubel glaze it because it's on the (sunny) north side and a double glazed sash window would be heavy and cumbersome. The plastic film is available from Community Energy Action in Christchurch and here's some other comments about it.

The bubble wrap works OK - it does gather some condensation on very cold mornings. Given that the price is not much better than the acetate option, and the look is not appreciated by some observers... I will favour the first two options.