I found my first couple of years the quickest... I started nearly 3 years ago and after a month or two, I'd got back to GGGG, and GGGG Grandparents. The only limitation was that I didn't find out about the IGI until later, and not all the censuses were available. Ancestry had the 1901, 1891 and 1881 but no 1871 for Yorkshire, although they had Warwickshire so I could do some of my tree at that point. Now things are going quite slowly - pretty much every line that I'm stuck on, I'm stuck on for a reason and perhaps need to go and look at actual parish registers to get further back.
The internet just makes it far easier to do research - you don't have to commit a certain date to go and do something as you can do it whenever you like. It makes it very difficult to do research when you need to go to a different place to research different branches, and you often need more than a day to get everything done. Parish records are lacking online - I really hope someone (probably Ancestry) will transcribe them. The IGI has its limitations: Marriages state if they are widowed or not, and who can write, and this information is omitted. In the case of widowers, it's key information to get further back. Deaths before 1837 are quite sparse, as they're not on the IGI. The NBI is available, but the church burial records often give a cause of death, which can be very important: I found one for my GGGGGG Grandfather who apparently fell down the coal mine in 1805. It would save a lot of hassle if some people transcribed ALL the information in parish registers - It's a lot of effort, I know, but there's no point in people constantly transcribing them and omitting information, as it just means they'll have to be transcribed all over again in the future. FreeReg is a great idea, but people don't really have a lot of spare time on their hands. I think it would be much better if it was lottery funded (or is it already?) so they can at least cover travelling costs for transcribers, or preferably pay them. Anyway, sorry for going off on a tangent

Andrew