..but for me, the choice is usually clear cut.
For family summer camping on organised sites - our giant Coleman 'Mosedale' 5 man tent, or the 'Mosedale Whale' as I like to call it. Takes 20 minutes or so to set up, but it provides us with a large midge free space to hole up in if the weather is poor and they are biting!
For 2-3 person 3 season camping I have a Coleman 'Phad 3' tent that I picked up on ebay for £40 - hardly used. Easy to pitch, big enough for 3 people + dog, large porch and light enough (just) to carry at 4kg.
For solo trips I have a StormShield 'Ultralight' 2 man tunnel tent purchased several years ago from Millets for £60 - not a common tent, but sturdy, dead easy to pitch, well designed with alloy poles and full midge netting door, and not too heavy at 2.2kg. Big enough (just) to get dressed in without performing contortions. I'm quite a fan of this tent, despite it being a bit on the heavy side for solo use.