broad question.
i love delays. i had owned a handful of pedals, but only had the Einstein in my rig for a few of 'em - the DD20, Timefactor, Carbon Copy and the Line 6 DL4
I guess the one i would try to turn you onto if i worked at Guitar Center, it'd be
the Line 6 DL4. It is very intuitive and easy to use, sounds great. The ease of use of a thing like a delay pedal really is a bigger bonus than you'd think, as it doesn't take the amount of user-manual time and 'effect experience' to be comfortable with out of the box, y'know? I'm going to assume that y'all know what is involved when buying a DL4, so i'll give my thoughts on the others. All Units reviewed are all gig worthy and will take a lot of use or abuse in order to break.
The DD20 i felt was a less interesting effect, but did the job excellently and the LCD panel is very useful. Delay tonal variety is a little bland compared to the rest, even the Carbon Copy - a standalone analog delay. There wasn't a very big difference in tone between the Analog and Tape models, and the rest of the modes are Digital voiced - quite lame in my opinion. I owned it only for the LCD display, as my band plays to a click and the display makes it a cinch dialing in bpms for songs.
Carbon Copy - a purchase only because all of the modelers do a good job of 'copping the tones', but a real analog delay has something special about it; probably a combination of the coloration of tone and the warmth that the degraded repeats make the electric guitar a very fun experience. No model can replace a good analog delay, and between this,
the Memory Man, and an Ibanez Keeley (kitchen sink modded) AD9, the Carbon copy is the one that's still around. I admit that i traded the Memory Man in to get the LCD display on the DD20, but I've missed it ever since. The Keeley colored the tone TOO much, the loss of high end and signal compression introduced made it very noticeable when disengaged, and the lack of delay time was a big turn off for me. Only cons about it are the way the modulation controls are only adjustable via internal trim pots and some people will still think that it colors the tone too much. To me, it's a great analog piece for the money.
The Timefactor
This thing is a blast if you're into delay tricks. The design of it being a twin parallel delay allows you to do some very mind blowing things in comparison to two individual delays in series. I wont go into what the difference is between parallel and series configurations, but it helps you do things like polyrhythms (2:3, 3:4 work so wonderfully), or subtle things like dialing in a slapback delay to thicken the note up and dial in a longer separate delay perform the rhythmic repeat (meaning you can officially nail the 'Streets have no name' delay idea). That's only the tip of the iceberg of how one can be creative with such an effect. The delay tone is rather accurate and clinical on some settings, but it is überflexible, and you can dial the harshness out. The "Vintage/Analog" setting is modeled after something like the TC 2290, not after a Memory Man so it is still a bit brighter than a traditional analog unit, hence the reasoning for owning a Carbon Copy also. The Looper isnt as utilitarian as the DL4; it has a short sample time which you can increase in a similar fashion to the DL4's, and it lacks the cool reverse setting that the DL4 has, but you can do cool stutter/sample tricks as you can select the start and end of the loop down to the second. Using the Timefactor's looper in conjunction with the DL4's is one of the best things about jamming with my friend who owns the DL4 himself. The Timefactor overall is an awesome unit that I personally needed to have, as I love delay, but between this and the Carbon Copy, I dont really lust after delay as much - contending units such as the strymon and the Empress Superdelay are awesome in their own respects (some even would prefer either one), but if you're spending ~$400 on any delay, any educated choice should satisfy a reasonable guitar player. The firmware updates on all their stompboxes (i have the Pitchfactor also) have all been excellent and only increased the feature base, so personally I'm very happy with my setup right now
I have mine hooked up to the Serial Loop along with the Carbon Copy. Changing the unit's level between instrument and line level is nice and easy via two switches on the connection panel.
side note - the Strymon Timeline looks BANANAS (is also updatable!) and the Superdelay sounds excellent - i've demoed it at Ludlow Guitars NYC. It would be the perfect compromise between almost-analog warmth (its digital) and the features of the Timefactor - programmable presets, parallel twin delay lines, filtering, etc. The tone is what really rocks on it, I'll admit that i like it better myself and wouldn't mind it on my board, but it too is ~$400 and the tonal difference really is not enough to wrap my Eventide up, sell it, and buy the Superdelay.
All in all, gimme a Timefactor and an Einstein, and I could be super happy! I am right now with my setup... GAS is cured, but like any addiction it's a lifelong struggle
TL;DR? Fine! - these are legit reviews and worth the read!
Do not use these unless you plan on running the delay in the PARALLEL LOOP, set the effects unit to "Kill Dry", and buy an Ebtech Hum Eliminator:
i need the effects!! they indulge me