I agree with Si the Luxe is UBER smooth, efficiency is ok but customer service is very hard to come by in the UK, as DLX is a US based company, the only service you may find is techs in the UK or someone who has a lot of experience.
As with Planet they are Top notch, you cant go wrong with them, all my guns have been planet and all have been faultless. Im not planning on switching company atall. I shot an Etha sunday and they are awesome. They were out-performing Ego 11's and Geo 2's - paint was very brittle and was coping very well with it. They are definatly worth the money, especially with the efficiency, build quality and especially customer service.
If your only going to be doing walk-ons, i know you havent opted for it but i'd go with the Etha as its a perfect scenario marker at a very affordable price. I'm getting me one after Xmas at that will do me well for Scenario and Sup-air.
Like Si said, Paint quality and barrel is the bigger factor, so it be best to save your money, get the Etha, and buy the best paint you can afford and size the paint to match your barel to get optimum accuracy and efficiency.
Hope this helped,
Josh.