A mate of mine used to have the red one,and left in near to the Window in his studio,part of the casing had been partially faded by the Sun over the years and the casing went pink....He of course advertised it as a special Pink model and some mad collector guy bought it off him for £450 back in 1998
As for the sound My friend used it mainly for blips and beeps more than actual playable sounds As it only has 1 Oscillator,most of the timbres it created were very much similar to the TB303.squeclhy acid lines and sub basses and i suppose now more aimed at Techno or dance it has no patch memories either so everything has to be done from scratch!!
I would expect it to be more of a collectors item nowadays than actually useable,I can't say its the type of synth i would want to buy other than for nostalgic reasons,i would expect to pay anything in the region of £250 upwards depending on the Colour(grey is the common colour)with the Red and Blue Models fetching a little more cash,an additional modulation grip also adds to the Price too and a Midi retrofit will bump the price up even higher(if you can find a retro midi'd 101) as the original 101 dont have Midi,so its very much a hands on instrument,although it does have CV inputs so shouldnt be too hard to hook up a Midi/CV control convertor for external sequence control
Worth owning if you can get it cheap enough,but its mainly a Dance type sounding machine,but i suppose you can use it in whatever music you do if you know how to create the right sounds...
Somebody on the old forum said Jarre used one on WFC!!!Not sure where,but he did have one at Docklands(Sylvain Durand played it during RV4)