I have used Liquicolor mainly but when I have a Roland technician work on the machine they insist I switch back to factory ink so I‘ve bounced between the two.
My SP540V seems to run cleaner with the LQ meaning there just doesn’t seem to be as much stray ink splattering around. Other than that I really don’t notice a difference between the two.
Concerning the price, I do try to keep track of my ink usage and it seems I use slightly more when using LQ but that could be coincidental with other variables.
The people at Solaris are very helpful if needed. I believe it is a lighter viscosity than Roland ink.