I've seen similar boxes to those MDF ones on the link in some record stores - they were very shabby in construction and were quite expensive - I couldn't see why people would buy them... If you want something as basic as that get some MDF and borrow a drill and make them yourself for a few quid each...
I think it was only a while back this discussion came up but anyway... At home I store about 1000 records in Ikea's Expedit bookcase http://www.ikea.co.uk/product_presentation/show.asp?productnumber=00009711&type=III&id=3039,3078 - they only show the 4x4 one on the website but there is 5x5 one too (records take up just over half of the unit). Its very strong and sturdy and I am very happy with it. I reckon you can store 50-100 records comfortably in each section meaning you can in theory get 2500 records in the 5x5 unit, but remember that is going to be a huge weight so think about it if you are not on solid concrete! The rest of my records (about 10,000+) I store in a rented storage unit which (1) I feel is more secure than keeping everything at home (2) having avoided having to move with all these records once has provided itself very useful (3) I don't reckon the weight of all these records upstairs is good for the house! In the unit I use cheap shelving units from DIY stores (Homebase and Wickes) which were about gbp20 each and store round about 1000 records each. Unsorted stuff I put temporarily in plastic crates which I got at gbp1 each on Milton Keynes market about 4-5 years ago and are still going strong! David