I like both of them for different reasons, but definitly play on laptop more.
1. You can poop and play.
2. My laptop is way faster and newer than my old destop.
3. All of my player notes are on laptop.
1. Bigger screen.
2. 4 tables are way bigger on desktop than laptop.
3.Can fit 9 tables with no overlapping, 12 with semi-overlapping, 16 is managable with alot of overlapping.
I rarely use my desktop anymore, don't really need more than 6 tables up at a time. Seems when I add more than 6, I lose more than win lol.
As for the concentration part, that's all up to you. I can sit on my desktop, watch tv, run into the kitchen to get water, or run to the bathroom really quik. But that never guarantees I am not gonna put AA in the muck if I don't get back in time. I have missed hands on the laptop too, though, because carrying it around is a hassle sometimes.
So to conclude, you really need to be distraction free at all times, whether on the laptop or desktop. I always seem to do much better during a tournament/session if I get a HUGE glass of water, ashtray, lighter, cigs, gnob(backwards), and 420 within arms reach, and have eaten before the tournament/session. With the exception of during a tournament they have the 5 minute break, sometimes i'll refill my H20 or grab a snack. AND with the laptop I can sit in the comfort of my own bed and do all this, and definitly with the tv off for the best results.