I purchased my first home computer - an Atari 800 with 48k in December 1982 in Hammersmith, London - I forget the exact price I paid, maybe around £700? as the price was dropping slightly then, with 410 recorder, Shamus, and Star Raiders and Pacman carts. It must have been around a couple of years? I spent reading about home computers in computer magazines ... and tried looking at what computers were available in Dunedin, Christchurch, Auckland, LA (couldn't actually find a computer store there...) and somehow I made up my mind in London - to finally buy a computer there...
I lived in Hull for about 10 months - so around June? I did see a C-64 running - but there were little games for it, at it's release time.
I did make the point of having the 800 converted from PAL-A to PAL-B so that it would work OK, back in Dunedin. A few years later I did get an Atari 600XL briefly - had it upgraded from 16k to 64k internally. Also had a 800XL too - briefly - then a 130XE. When games were scarce for the Atari - I did have a C-64 for about 6 months - first with cassettes - then got a disk drive and action replay II cart - so as to speed the thing up.
I was an early adoptee of the 1040ST - and later changed over to an Amiga 500. I eventually got a Sega Megadrive and a few carts - but it was the Super Famicom that really caught my attention - and delivered the high quality arcade conversions - of late 80s coin-op games, and early 90s? I got a disk drive device for it - which got over the high cost of carts, so that you could run ROM files from floppy disk.
I never had too many systems at the one time - as I could not afford that, and sold my older system/computer.
I did regret selling my Atari 800 - I did have a happy 810 drive, and a 1050 US Doubler one - but I simply couldn't afford to keep it.
AtariBLAST! does run from a flashcart (such as Maxcart?) - and I don't have any Atari hardware anymore, so I don't know how to actually run it via flashcart. However the first version, ie. GTIABlast! was designed to run within 48k from disk. Later versions do not.
All versions can be found at the http://www.playsoft.co.uk
You probably missed seeing the Techbytes converage of GTIABlast! on TV3 in Sept 2013... but they hardly showed much of it..
I use the Altirra emulator to run the test programs of AtariBLAST! with - on a 40" LCD Samsung TV - ie. via my laptop. I only handle the graphics designs - and don't have anything to do with the technical/programming side of it.