From what I have seen and heard on here, they are much of a muchness. First have the more modern traction and better pay, but this may possibly be nullified shortly as Northern are allegedly reviewing their pay structure due to losing so many qualified people to other better paid TOC's. But they both sound like great companies to work for. I suppose it will depend what you would be looking for from the job to make you happy. For example, would you a) commute up to an hour each way for 3K - 10K p.a. more or b) settle for the job on your doorstep? Personally, I would take option b) as I have kids and after commuting costs, would see little additional financial benefit. After that, it comes down to what the job is like, which in my opinion, only you could decide, as this may be shift patterns, colleagues your working for, environment, routes, etc. etc. etc. and is very much down to you as an individual.