Deane, I once thought as you do that the OS was at fault, but I have since learned to use this tool within the limitations of its hardware and software integration. Many of today's keyboard arrangers seem to be synths with some computer animation added. The Ketron approach is more like a computer with keys. It's a Lynux system, and its limitations are, like any computer - the RAM, Speed, and storage. I had one about 5 years ago, and returned it because I thought it wasn't ready, and maybe a few things weren't but the biggest thing I have learned this time around is this: Once you learn it's capabilities, and perform within the limits of these parameters, it is remarkably glitch-free, like most of the other big boys in the mix. What computer DOESN'T have bugs early on?
Sorry, I meant to say what WINDOWS computer. We all know Macs are perfect. (NOW I have your attention, huh!) ... moving on:

NO - I AM NOT ENDORSED BY KETRON (but I'm hoping that may change one day)

I am a live player, and like many of you, I sometimes act impulsively when performing. I'll give a few examples of "Glitches" that aren't glitches.
I'm only speaking of the SD7 at this time, because that's what I have the most experience with. (Had an X1, and SD5 way back when)

1) sounds are delayed, or rhythm hiccups when selected.
*** Ketron uses live samples, and need to be loaded each time you use them. The internal RAM can hold 2 sounds at a time, so if you are switching between 2 selected sounds, there will be no lag time. IF you select a third sound, it has to release one sound and load the newest selection, so you get a slight delay. This is a teachable moment in playing an arranger with live sounds. As is the case with ALL samples, some are larger than others, and the load times may vary. I have learned to audition the sounds I like the most and put them in my favorite voices section for easy recall. If it's crucial to the beat and I need instant ON of a sound, I make sure it's one of the smaller samples. Some sounds have minute nuances that won't be missed in certain applications, like the key noise on a Rhodes, or pedal resonance in grand pianos - If you need a quick change for effect - choose a more workable sound.
-- A good analogy would be documenting the existence of an eagles nest that is a very hard climb to reach, so you bring just your phone or a small point and shoot camera, instead of a larger, heavier DSLR, tripod etc. - This job requires a quick snapshot to prove the thing exists .... not a full studio layout of the intricate weaving of the nest. Right tool for the right job. (My hope is that the SD60, with it's dual core processor will reduce this issue a bit, or eliminate it entirely)

2) Vocal Processor is not a TC Helicon, or a Digitech, or a Roland, or any other unit you've owned. Learn what it can do, and use it as such. It's a fine effect unit, and although slightly different from the pack, it's completely musical, and useable.
Usage analogy: If your quarterback has reduced vision on one side - PROTECT THAT SIDE the most. Sometimes you have to make adjustments for conditions. The end result of using a Ketron Voice processor can be 100% professional. It will NOT operate exactly like the competition. Make the choice to either embrace what it does best, or choose another option. I am learning more things that I like about it each day. Future updates may make it even more compatible to more users.

3) The sequencer/player work a bit differently than some others. This unit needs to "look for" the files you want to play, just like a computer, so make it easy for the player to "find" them by organizing your disk drive. The default location is the Ketron drive, but if it's not large enough for your library, all you need to do is select the drive you want to point to at the start of your session, then if will always jump to it. There are THREE USB slots - more than the rest.

There are many "things" that I'd love to have on the instruments I own, that the manufacturers have decided not to implement. This is their right. As a consumer, it's my job to do the research on what instrument will fill most of my needs before purchasing. After owning almost all of the top choices in past years, I have only a few dealbreakers, and the rest ... I'll deal WITH. For what it's worth, here's my list of "gotta haves". (Sorry if it's repetitive)

1) Speakers
2) Solid key feel
3) pro quality mic input with great effects (harmonizer a plus)
4) portable (subjective) The SD7 is longer than I'd like, but the layout is very ergonomic, so I deal with the extra six inches. (That's what SHE said?)
5) Great sounds and rhythms
6) On board song player

Other things I LOVE, but aren't deal breakers:

1) sliders for real time control
2) touch screen
3) second input for mic or guitar
4) stereo aux in (for iPads, and such)
5) on board digital recorder

I'm rambling, because I'm avoiding doing the dishes, and the wash ... thanks for the diversion! Hope this helps some of you in your quest for excellence. I must admit, I was very surprised that I like this unit as much as I do, given ho much I love the Korg PA4x. (but NO SPEAKERS) Perhaps, given the current state of the business, my mindset has evolved to a more mature state of being, and I'm able to really focus on the things that will enhance my shows. (Even if they are largely from my living room for a time) There are many choices that certainly can do this, but right now, the SD60 looks like my "Nirvana" ... Time will tell, but I'm very optimistic.

Truer words were never spoken Don.....+1 buddy all the way.