is there any real difference between the 4th and 6th editions of the book molecular biology of the cell?
0815344643 (6th)
0815332181 (4th)

I can get a physical copy of the 4th edition for about $10 or the 6th for $100ish and was wondering if there is enough new info to justify the price. the 4th edition is 20 years old but if there isnt a lot of new material in cell i dont see a problem. its not strictly for school as I plan on reading this in free time so im not worried about problems being the same.