I bought my Stokke pram from them in the summer. No problems at all. The pram has to be ordered 6-8 weeks before you want it as they don't hold stock of the Stokke. We managed to get free delivery with an online code. We found the staff friendly and knowledgeable.
I've known lots of people buy from them and nobody has said anything bad about them. Did you read their t+cs? Seems clear on there that they may not have the item in stock and there are a few suppliers it says 6-8 weeks for. I don't think the issue here is with how 'reputable' the company is, more that you don't think that their website is cleat enough.
Please be careful when purchasing any products from the Glasgow Pram centre www.pramcentreonline.co.uk . They seem to be selling products cheaper then more well known retailers but in fact they just take your money and don't actually have the product in stock, and trying to get your money back is a whole other story, I still haven't been reimbursed and I don't have the pushchair I ordered either. Considering how expensive prams can be its a very costly mistake. I would urge all mums to only buy online from companies that you know are thoroughly reputable.