I took the LNAT about 2 weeks ago, and I'm applying to Cambridge, LSE, UCL, KCL, and Bristol. Time really isn't an issue for the multiple choice section, I had about 20+ minutes to review my multiple choice questions. However, the essay does have time constraints. It really isn't that bad though, and if you spend 5 minutes planning out your argument, then you will be able to finish it. There is too much hype over the LNAT, it isn't a decisive factor in your application and although you should take it seriously, don't beat yourself up by 'studying' for it. I think it went quite well and I did 2 practice papers.