Casio HT-3000: More like a toy synth (home keyboard with synthesis), at a time when this (new/late 80s) was all I could get - Loved it though - sold
Roland D-50: Loved you since I saw you in a magazine, knew I couldn't own you until 20 years later... wasn't disappointed when I did. Cheesy 80s presets are fun for nostalgia, dump them and uncover the almost 'virtual analog' core and MASSIVE synthesis possibilities inside that most newer digital synths just don't have.
Roland JX-3P: Love it and also wish it had more features (like the 8P), 3P sound has more edge, more retro-ness, and very cool (jupiter 8!) filter... Get some nice riffs running with the limited sequencer. If forced between the 2 JXs - it would be hard, but I guess I'd keep the 3P for it's more unique 'classic' sound. 8P is a way better all rounder though with lovely features.
Roland JX-8P: Monster version of the 3P with some changes. Sound is softer, smoother, more epic. Has spacey pads coming out of it's *** and can sound very agressive in unison, good for solo playing also.
Roland Juno 6: Maybe I should never have sold you, but I did grow tired of no patch storage, no midi and other quirks... no doubting the sound though. Not as flexible (or interesting as my JX3p/8P) but definitely had the edge for those fast env basses and cool arps (which isn't really my music anyway) - sold
Korg M1: A classic i'm sure... some nice sounds... but I can't get past the way it feels more like a 'box full of samples' moreso than any other of my synths (inc the SY/TG). It's got the worst filters of the bunch. Nice design on the back edge, nice font, c**p buttons, c**p keys, clattery, echoey, hollow - also gives me an impression of some 'disconnection' betwix keyboard and internals (maybe a 'drive by wire' feel) - SY feels a lot more hands on/organic and nicer set of sounds to boot.
Yamaha TG-500: Nothing wrong with this as a box of sounds rompler with great filters trying their best to make it a 'real' synth... Sold it as had moved to software only at that time (2000) - sold
Yamaha SY-85: Wanted some of my old TG sounds back + a very nice keyboard to 'write songs' on (just as a compositional tool). Also of course, great filters takes off the digital edge (a bit), and I really like it, but it's not D-50 when it comes to synthesis
Yamaha DX7 II-D: The mysterious beast, I'm getting there - having ditched/avoided any overused 80s sounds (mostly) and now finding some AMAZING textures I can't get anywhere else... must add a touch of outboard (reverb/delay) and it competes easily with younger synths. It does weird stuff like no tomorrow - using it for E-Piano and Tubular bells is a waste of it's potential in a modern context. Misunderstood, and a marmite synth (love/hate). I love it! A legend (albeit the mk2) in my lifetime and I wanted one since I was a young kid! I must stress while I also like the mk1, the mk2 does it for me due to the layering and other (important) improvements which I use all the time! A mk1 may be less useful to me but nonetheless a classic

Yamaha AN1x: My newest purchase, and quickly becoming my all rounder/favourite machine to work on. While my D-50 still has that magic 'something', the AN1x isn't magical to me, it's a very very good tool. It's sounds are perfect for music making and though it lacks the real welly of true VCO analog it's perfect in most cases 'in the mix' where it counts. I couldn't be without this now, and this would be one of the synths I'd save first in a fire! (not least of which because it's cheap plastic upper casing would melt while my others would withstand the heat better) - oh and like it's look, and it's colour, and it's 'light' keys and it's feature set. It's like the 'heart' of my synth world now - I want to control other synths with it (arp and knobs).
wow, so much for 'one line' reviews - sorry people ;0