I would like to remind Franco that you can't have it both ways. In this case you can't say you say you're affiliated with Tarptent and then say this is an independent opinion. Once you've made an association, independence is no longer an option.
That said, comparing the DR to the Haven is like comparing Apples to Oranges. The simple fact is they are shelters just like the other two are fruit. Beyond that they are very different beast with different capabilities.
Taken together, the Haven tarp and nettent form a spacious lightweight double wall tent. For many who hate single walled shelters, this is a bonus.
The design and shape of the Haven is to maximize internal space while minimizing weight. To that extent I think it works.
Some people will simply buy the Haven Tarp. It's shape and size make it a spacious 2 person tarp that's simpler to setup than most tarps and provides significantly more weather protection.
Others will buy both products and then pick and choose under what conditions they will take one or both items. During high bug season, the nettent is taken to provide bug protection that is significantly more comfortable than using 2 bivies. Otherwise the tarp is taken alone.
As to which tent fares better in severe weather also depends upon your point of view. When setup with two hiking poles, the Haven will provide a very secure shelter that will handle winds with ease.
While the long arch pole of the Rainbow does provide an excellent tension source, it's narrow diameter is no match for the strength of dual hiking poles.
Also I would note that if Haven is a poor chose of shelter for bad weather then the other long tunnel like Tarptents such as the Cloudburst, Squall, Contrail, etc. would be absolute disasters in anything worse than a summer breeze. Compared to these shelters the Haven has a considerably smaller expanse of unsupported fabric.
In any case, Henry and I will be getting together in the next couple of weeks and I'm sure we'll have a good laugh at these comparisons.
Ron
Six Moon Designs
PS: To answer Lynn's concerns, the height of the end walls of the Haven NetTent is 12" at the end of it's 90" length. The actual Tarp canopy extends another 5" beyond the NetTent is a couple of inches higher. This provides plent of room for the thickest pads and sleeping bags.
As to a porch. The Haven NetTent is reset within the tarp and has pretty vertical walls. It's pretty easy to get in and out without getting wet or setting up some fancy rigging.
Also since the NetTent is hung within the canopy, it can easily be taken down and stored when the canopy is wet or it's raining and be kept dry.