it's not your imagination, it is faster, more stable and more secure and has the added benefit of loads of very good and useful add-ons that can easily be installed to customise it
One thing I like Firefox for is that it is dead easy to enlarge the print ( a boon for us oldies). Simply press Ctrl and the + sign and hey presto it goes larger, repeat it and it goes larger still. Ctrl and - will reduce the size and Ctrl and 0 will put it back to where it was originally.