Hi!
I am using the precursor of the Impact Twin, the Konnekt 24D - on PC, Windows XP prof., SP2, since 2 years now. Never had any problems with it, and getting an acceptable latency of around 5 ms (I don't use a lot of midi, though)
the preamps are thought to be pretty clean and the conversion seems to be very good.
The routing possibilites within the Impact Twin are quite good, as I see in the description.
I think, for the money, you get a lot of quality regarding the preamps and the conversion. Also, the TC effects are very usable (channel strip and reverb) - from the manual, I didn't understand, if you could use he channel strip and the reverb after recording (like a plugin) for processing the recorded audio. But with the new drivers, you get the M40 reverb, Resfilter and Assimilator as plug-ins.
I also used the Konnekt 24D in combination with an ADAT interface to record 10 channels simultaneously - worked like a charm.
Some people have problems with general perfromance, though, and TC is not too fast with driver development, although they published a couple of new drivers since the konnekt series was released (maybe also take a look at the forum)
another thing is, that not all firewire cards seem to work well with the konnekts. A Texas Instruments chipset is recommended (my laptop has that, and as I said, I never had any problems).
edit: I see, you're on mac. the agere chipsets seem to work fine with most konnekts, there are no 64bit drivers for mac available, yet.
see here:
http://forum.tcelectronic.com/viewforum.php?id=3
Another downside is, that the headphone output is hardwired to the main outs 1/2. Thus, the main volume knob on the front controls the volume for both simultaneously. A solution to control both volumes independently would be either using the TC level pilot (as I do, feels awesome) or using the main outs 3/4 as your main outs, but then, you could control the volume only in the software (TC contol panel or your daw)
This would also be the way to route when cueing (e.g. in Live). Also, the inputs 3/4 on the rear are not very hot (use it for synths and it's o.k.)
Stability- and performance-wise, there may be some problems, but I think only for a minority of users. But as always - best to try before you buy. I didn't compare it to it's direct competitors (Duet or Ultralite, as I see it - the Ultralite providing a lot more in- and outputs). Latency-wise, I think RME interfaces (firefaces) work best. Would I buy the konnekt again? Probably yes.
my 2 cents, hope it helps with your decision
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