In reply to Dark-Cloud:
I'll have pretty much exactly the same dilemma in 12-18 months time when my TNF Tadpole 2DL finally needs replacement. They are a classic, reliable and proven design and TNF were idiotic to discontinue them!
My short answer is don't spend £150. Either spend £100 on a Vango Tempest 200 on the best deal you can find or spend £250+ on something properly decent like an MSR Hubba Hubba NX2.
I spent ten days backpacking in the Pyrenees in a Vango Tempest 200 back in 2010 and it's a perfectly serviceable tent. I've pitched probably several dozen other tents over recent years including most of the Vango range and it's the closest to the genuine 3 season performance of the Tadpole. However, it's still a cheap tent and compared to your Tadpole you'll notice the difference.
It don't rate any of the Wild Country tents that highly. Basically, they aren't any better than the Vango equivalents but generally cost more. I've looked closely at the Vephyros and Trisar and both have issues. (Also avoid the Terra Nova Voyager, it's far lighter than the Tadpole but inferior in pretty much every other respect and stupidly overpriced.)
The best option is probably to buy another Tadpole in near new condition second hand. If I can't do that, I intend to pay a bit more for something with equally good or better build quality.
Post edited at 12:23