I use it as my main audio interface for mixing, but I bought it for occasional recordings, with the intention to record through the UA unison plugins. The console application gives great flexibility. The only thing that left me wishing is that it has 6 DSPs: It might be enough to record, but in my opinion this unit should have had 8 DSPs. I always end up running out of processing. For that I had to buy a UAD satellite.
Agreed, price-wise the interface is not on the cheap side, plus adding DSP power requires to shell out for even more. But then consider this: every now and again, I use other brands of plugins, and invariably when I replace that with a UA plugin it just works better 99% of time. So if you only need inputs to record, I reckon you have options with other products. But if you also care to get world-class sounding plugins there is no doubt you need to go UA products.