The Manor are always doing themed weekends too - it's on my list of sites i want to visit in 2015.
As people have said above, they are quite different game styles:
I enjoy the adrenaline of CQB - if it's a good site, with lots of hiding places/rubble/barricades/etc then you never know where your next opponent is going to pop up from - it gets my heart racing and my nerves jangling...
But I also love the tactical aspects of woodland play - if the site is big enough then you can operate at distances where camouflage is effective without having to be immobile in a thick bush - the whole outflanking and coordinated attacks malarky, ie proper tactics, is great fun - and whilst you can work in small teams, or pairs, in CQB, especially for room clearance, you're often in small spaces and/or choke points which restrict what more than 2 people can do in conjunction, whereas outdoors you can occasionally get a degree of cooperation amongst loads of players...
I agree that room clearance in teams of 3 or 4 is some of the best airsofting going, but when a plan involving 5-6 groups of people comes together, when everyone does their part and you rampage through the opposition like Harold Shipman through an old folks home, even if you're not in the front line getting the spectacular hits, it still feels great!