Aaaah - I have fond memories of both machines. I spent more hours hunched over the keyboards of both than I care to remember. I had two dream jobs while I was at school - Software Engineer or Flight Engineer, it was these hours that made me choose the former.
As has been already stated you are not really comparing like with like. The Beeb was designed for the education market and the speccy for the home market.
Assuming that we are talking bog standard BBC model B against bog standard Spectrum 48k
The speccy was cheap - the beeb wasn't.
The Beeb had a decent keyboard - the Speccy didn't.
The Beeb was hugely over engineered - my computer studies teacher threw one across the computer room in a rage and it still worked - try doing that with a modern PC!
Not only did it have a "proper" disk drive interface, but it also had a serial port, a centronics (parallel) printer port, a hugely versatile user port, a tube port for connecting additional processors, basic networking (Econet) capabilities and made a funky sound when you turned it on.
Having said that the speccy had 48k of memory to the Beebs 32k and there was a better variety of games for the Speccy. I even had a rudimentary word processor and Epson FX80 printer connected to mine before I saved enough pennies to buy my Beeb.
Later Beeb versions were seriously impressive (apart from the appauling Master Compact) the Master 128 was a fantastic machine and could even be made PC compatible (to a fashion) with a 80186 processor and a hard drive (under ADFS).
Sorry for rambling - it brought back memories
