2.5 kg is about 5.5 lbs. That is on the heavy side for a solo tent, but it's certainly doable if it has all the features you want. It really depends on what you need from the tent, where you are going, the climate, how long the trip is, etc. If you're going on a summer trip in areas where you know you probably won't encounter any extreme cold or stormy weather, then a very lightweight tent is probably a better option. Why carry the extra weight if you don't have to? But perhaps you are going on a trip in the Spring or Autumn, in areas where it might get nasty (e.g. the Rockies or Yellowstone), or if you just want the extra space, or whatever, then a heavier tent can work for you. Every tent is a compromise, you just have to work out what compromises you're comfortable with. What's that saying? Something like "light weight, high performance, low cost - pick any two". So for many people, their absolute no-compromise criteria is the low weight, and that determines which tent they take. But others like to have a tent that will see them through rough weather, or give them more space, and they end up with a different tent. I think regardless of your preferences, you probably don't want a super heavy tent on a bike tour, but 5.5. lbs isn't insanely heavy. I just bought a Hilleberg Soulo (4.5 lbs) which I will probably use for solo trips, and an Allak (7 lbs) which I plan on using when touring with my wife. Both are heavier than what many people would care to stand, but I like the fact that these tents are strong, freestanding, and will stand up to just about any weather that I would care to be out in. I would probably take something lighter and more airy if I was going anywhere very hot and very humid, though - you always have to figure into the equation where the tent will be used.

Neil