For a bricks and mortar shop who are going to offer you a lot of advice, viewings, etc that is not a bad price. Particularly if you get to see the actual unit you are about to buy before you take it home. About the cheapest I have seen is £1030 delivered
http://www.robertwhyteltd.co.uk/robe...uct.php?ID=136
As for angle correction, the panasonic can do this and still output a straight picture no problem. I have a panasonic 200 (vertcal keystone only) and from my playing about keystone is not the way to go. For starts because it is at an angle the distance to the screen varies across the image resulting in loss of focus, at 15 degrees I think this will be quite noticible. A couple of degrees is fine, but I would worry about 15. The digital correction on the panasonic corrects the image by cropping off pixels to make the image square, to do this it must compress part of the image. From my playing around, even utting the correction on it's first notch makes a visible reduction in picture sharpness, particulalrly on text.
Keystone is a great feature if you want to take the pj to your mates for the evening and stick it on a coffee table, but for a permanent position I would do my very best to avoid it. In that you have built yourself an entire cinema, I am struggling to understand why you can not place it square on with the screen?