Got to be Sinclair machines, they were a good all rounder, most of the kids at my school had speccys. The C64s sound chip was very impressive but I found the graphics a little chunky despite the colour but did have some stand out games like turrican, Gianna sisters and creatures.
I started out with a 16K rubber key model as the family had just updated their 48K rubber keyed 'beermat' speccy to the new plastic keyed version which I would later inherit.
I then got my first propper speccy which was the 128K and then later got a +3 for Christmas. This was a great machine but by then Sinclair had been bought out by Amstrad and the build quality really went downhill. I had problems with disks reading and games loading till the end and resetting (common problem). For me the king of spectrums was the black 128K+2 with tapedeck built in.
The multiface 3 as mentioned was a great device that allowed you to backup your current RAM to disk so you could effectively use it to save your progress and perhaps more importantly get around those horrible copy protection methods by loading the game then saving it.
Stand out games on the spectrum for me were...
Star Raiders II, Midnight Resistance, Magicland Dizzy, Rampage - 3 players on a spectrum!, rainbow islands, chase HQ, R-Type, Head over Heels, Renegade, Target Renegade, Jack the nipper,
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