Having encountered some recent unknown, in which IE7 had become unstable and froze from time to time - with the only recourse being "Task Manager" to close the programme - I took the plunge.
No visual difference, seems much more stable than my old one (as just mentioned), but most certainly seems quicker.
I'll play with the toys later.
All I really needed from you all, I suppose, was to NOT see numerous responses saying "DON'T DO IT".