Antimoon

Underrated analog poly. Capable of bread and butter sounds as well as some out there stuff thanks to the bizarre filter implementation. Really benefits from the tauntek firmware upgrade to add midi control. There aren't a ton of VCO-based polysynths that can be had for the price these can.

Just a DX100 in a bigger form factor. Outclassed by newer 4-op synths, but can be found dirt cheap. Definitely worth getting if you want authentic 80's and 90's techno sounds on a limited budget.

An absolute classic bit of kit that's supremely underrated. Capable of doing a solid imitation of lots of your standard analog polysynth sounds, but so much more on top of that. The synth has absurd modulation capabilities for something of its era, with 4 Envelopes and 3 LFOs that can be routed to almost any parameter. The oscillators are classic Ensoniq transwave synthesis fare, but paired with an analog filter you get some pretty lush sounds. The sequencer can be fun, and with good sound design and judicious use of the 8-voice polyphony, this keyboard can serve as a rudimentary groovebox. The thing I've used my ESQ-1 for the most is as my master keyboard. Not only do the keys feel great (though they're not weighted), but this is one of the few keyboards I've found that actually transmits midi note off velocity!

I think the R-8 is maybe the best drum machine of all time, at least in terms of feature set. It is lacking compared to others in terms of live performance tweakability, since you have to stop playback to edit patterns, but if you put in the time to program sequences and thoroughly learn the machine, it's incredibly deep and rewarding. Additionally, getting the expansion card from Waverex allows you to load your own samples, opening up worlds of possibility. People have made entire albums with the R-8, and it's a genre-defining piece of kit for early IDM.