I am just begining to use two 1010lt's sync'd via s/pdif. My experience so far with these is just don't drive them to hard. If you keep average signal levels at -18dbfs (peaks of course will be higher) or so, you will have plenty of headroom for mixing and mastering. The A/D - D/A converters are certainly not the best, but yes you can get really decent sounding tracks out of them.
Mine are connected to the "Direct Outs" of a Mackie 32 Channel 8 Bus. For instance Channels 1-16 on the Mackie each have a direct out going to the inputs of the Delta cards "Card #1, 1-8 then Card #2, 9-16. These are connected via 1/4" TS (unbalanced) to RCA. I just got inexpensive 8 channel 1/4" to RCA snakes, about 13 feet long or so. I have the inputs of the 101lt's set to +4dBu. IMO this is suitable for project work.
I think they sound fine. HOWEVER......I am having problems with pops and crack sounds while recording. I have traced this down to be a motherboard problem having to do with PCI bus timing, IRQ's etc. In my case (Dell Optiplex 320, P4 HT) I have not been able to get it resolved. So I will be building a new DAW in the coming weeks. Many people have had this prob, not just with 1010 or PCI in general. The prob with the Dell motherboard is that there is nothing you can do in the BIOS in the way of setting IRQ's. This means that it is only able to use ACPI, which is not working in my case. If you have a white box type motherboard (Asus, MSI, Gigabyte, Intel, etc) I would think you could overcome this no matter what with a decent machine.
I can put the cards in an older P3 866 and do not have the pops and cracks, of course it dosn't have enough horsepower either but proves the point, so I think the 1010lt is a decent product, just wanted to pass on my experience. Might save you some headache.