I have always been a big fan of the British styled bird hides with telescopic poles rather than the pop-up variety. I use pop-ups a lot, but my main portable hide is still a home made square type with upright poles. The advantage is it is easier to erect on a slope or rough ground as the poles can be adjusted and the height can be changed depending on what I am photographing.
I am in the process of getting a batch made for sale and the first one is ready, others should follow this week. It is made from army DPM patterned waterproof polyester and the telescopic poles of aluminium.
See http://www.wildlifephotographyshop.com/Bird_Photography_hide/p2203723_16496585.aspx for more details.