I have been having problems with dreadful slowness on Ancestry since December. I have been in email and phone communication with them. As far as I can make out, the problem is due to the huge expansion of the site in both records and members, which has overloaded their servers. However, this doesn't seem to be affecting everyone to the same degree. At one end of the scale there are people who have no problems at all, while at the other end there are some for whom the site is unusable, and Ancestry are baffled. They told me that they have a dedicated team working on it and that new servers are being installed.
It does seem to have improved a bit in the last day or two, but I doubt it will ever be as quick as it used to be.
Charles