The ASR is similar to its predecessors EPS and EPS 16 Plus. I prefer the Plus, because ASR can be a really buggy experience. They all lack resonant filters but can mimick that to a certain degree. Today getting one of these would mostly be recommended to hiphop producers. A computer with say Reason easily outperforms it. Fun for those new to sampling & keen on working with floppies and SCSI gear. Quite good back in the day, but flimsy quality. I have seen a lot of dead Ensoniq EPSes and ASRs.

Odd title for a sampler review, right? But its true. I started with it's predecessor, the EPS keyboard version, in the early 90's while studying music tech at the HKU in Utrecht, the Netherlands. Digital recording was just taking off and the school had a Sound Designer I system on a Mac IIci that allowed me to record any source with a decent C414 mic and bring it home on a floppy!
Unlike other samplers at the time the EPS could transform my sounds to true musical sounding instruments by carefully tweaking the transwave and modulation features. It had a onboard sequencer so simple to operate I could close my eyes and completely focus on my music!
The ASR is the same machine, but it sounds better, has more memory, and crashes less often. You don't need to stare at tiny colored blocks on a computer screen while producing music..try the ASR

This is probably one of the most underrated samplers to this day. Here's some notes from a long-time user after acquiring it in 1996: It took me quite a number of years to "master" this keyboard, but once you have the interface and directory memorized, and your workflow down, you can easily pump out just as much music as anyone. The biggest asset, as has been said, is the sound- there's lots of EQ and amp. The on-board effects are stellar and able to be modulated in real-time, even when sampling/re-sampling. Still, produces quite a lot of heat and is really too heavy for a lot of live gigging.
Despite it being known more for Hip-Hop production, i make all kinds of music on it, even complex IDM stuff. The sequencer is not the best, as when it loops back around there is a slight delay. For compositions, i encourage both quantization mixed with manually played parts. With some skill, the timing issue can be overcome with the ability to build loops and phrases, which it really was made for rather than individual notes. Basically, there is about a 90 seconds-worth of stereo CD-quality sampling, so you have to manage between the sequencer memory and the RAM. I have run into a few instances when there were quite a lot of 44.1 stereo samples spread between multiple layers and tracks and the sequencer locked up and it will get stuck in "Edit" mode. For the most part, you have to leave about 30 seconds of sampling time onboard to run several sequences.
Mine has never had a SCSI and i have never had a real problem with all-analog sampling, with the ability to resample through 44.1 effects. Neither have i ever cleaned the floppy drive. The only thing that wears out after regular use is the square buttons that get the most work; usually the Edit, Record and Play. The underneath housing seems to wear away, there is some wiggle and i had to tape them. Other than that, i pretty much have pushed this machine to it's limit year after year and it's still the sound-making centerpiece of my studio to this day.
As of 2013, i have encountered several ASR's being sold online for a few hundred dollars and for the effects and sound alone it is easily worth the effort. There may have been a few out there that did not age as well, for the most part i am pretty impressed with its durability, considering the various heat, cold and humidity we get in the midwest. I would even consider buying another, or the ASR-X. There really is no reason why one could not get exactly the sound they want with them.