Most lenovo ThinkPads are certified to work with Ubuntu.
And (for me at least) there are no better laptops out there. They should have all of your needs covered. I would suggest going for the T540. It's awesome.
I just upgraded (today!) to a Thinkpad T430S from a Dell Latitude E6410. I now have the ability to go to 16GB RAM and upgrade the processor as well. It is fully compatible with Linux and is one sexy 4.2 lbs laptop.
the Tx30 is "theoretically" previous generation, but the problem with the current generation of Thinkpads is the touchpad without buttons which is very bad (not like the macbook) as well as the fact that several of them have one ram slot soldered to the motherboard, so you cant upgrade.
Also, most of the processors seem underpowered. You will be able to find previous generation thinkpads for less than 800 euros.
Having said that, the Dell Latitudes are also fully compatible with Linux - but not as cool looking.
I would like to chime in and say, regarding ram slots and upgradeable, you just dont need that flexibility any more. Max out the ram on purchase and it will last you until you upgrade. Its very unlikely you'll be wanting for more than 16GB in 3 years.
While flexibility is always going to be a geek plus its sort of a thing of the past.
T430s here. Was running XUbuntu 13.10, now running stock Debian 7.4 (I don't like XUbuntu 14 one bit).
Really happy with it. I bought a T440 for someone recently, which is also really nice however it seems the RAM is limited to 12GB max (too little for my use).
I just went to Lenovo's website and spec'd out a T440. They seem to have two versions of the T440, the 'normal' T440 for and the higher end T440p. The T440 is very slightly lighter and thinner but has a 1600x900 screen, Intel graphics and is limited to 12 GB of RAM. The higher end T440p is 0.1 lbs heavier and 0.3 inches thicker, but comes with a 1920 x 1080 IPS screen, Geforce graphics and up to 16GB of RAM.
Ah, I did see the T440P but there was something that put me off. Maybe I got the weight wrong (thinking it was much heavier than the T440). Or perhaps there was something in the service manual (which is fantastic, by the way) - awkward HDD upgrade or similar.
As an aside, the dual-batteries on the T440 are fantastic. Though you do need to remember to disconnect the internal one when doing any work inside the unit.
Yeah I don't use the touchpad most of the time either. With a huge SSD and plenty of RAM, the i7-3520M T430S gets the job done.
I'm not entirely pleased with the screen quality, but perhaps I've been spoiled by the IPS display on my personal laptop (Dell XPS 13) and my desktop monitor (Samsung S24C750PS).
My one complaint is that the keyboard isn't as robust as previous models. After only a few months I already have some keys which don't work without a firm push. I could sent it away for repair (or replace the keyboard myself) but I can't afford the downtime and tend to use an external mechanical keyboard when I'm not travelling anyway.
With my Thinkpads I always get the international on-site warranty - it's well worth paying a bit extra to have someone come to wherever you are to fix a problem.
the Tx30 is "theoretically" previous generation, but the problem with the current generation of Thinkpads is the touchpad without buttons which is very bad (not like the macbook) as well as the fact that several of them have one ram slot soldered to the motherboard, so you cant upgrade.
Also, most of the processors seem underpowered. You will be able to find previous generation thinkpads for less than 800 euros.
Having said that, the Dell Latitudes are also fully compatible with Linux - but not as cool looking.