This is my opinion so please take or leave as you see fit..
The original 700 was a little mid-forward and possibly slightly old fashioned, but the overall presentation was huge fun, the response basically smooth with no nasty peaks or dips and of all the then new generation of £100 ish speakers, these were the clearest, the next step being something like MS Pageant 2's or the then elderly KEF Corelli's, which didn't quite have the 'enthusiasm' if you see what I mean.
When Mission chose to discontinue the 700, the 700S (or was it the 707?) which I think replaced it, didn't seem to gel as well, the rather spitty little tweeter so beloved of subsequent Missions then coming well to the fore I remember. First the HB1 took over and the body-stocking'd KEF models (Celeste III and IV?), followed by the rather thick toned cheap KEF Codas which followed. After that, it was open house We didn't sell Celestion, although I understand they were beavering away in Ipswich, designing and building some rather good low-cost speakers at this time.
Basically, we sold bucketloads of 700's with the likes of a NAD 3020 amp and Dual or Rega turntables. If you can re-foam them cheap enough and tart up the red-walnut cabs, I still think they're very worthy...
Tear down these walls; Cut the ties that held me
Crying out at the top of my voice; Tell me now if you can hear me