Glad to hear the ride isn't compromised. I had this type of lift on my old Trailblazer and it didn't seem to affect the ride. On my previous 05 Escalade though, the lift/leveling kit was a new key for the torsion bar, that made the ride horrible enough that I swapped back in the stock keys.
275/60/20? That seems an odd size. How about the more common 275/55/20? Those should be plentiful as that was what was on the previous 20" wheels that GM (and everyone else) seems to use or have used recently. That common 20" size is actually cheaper than the 17" size on the last generation Escalade. I was pleasantly shocked to find when shopping tires.
I plan to take the mint factory chrome 20s saved from my 05 and put them on my 07. The 22s are just too rough riding for me (not to mention ugly with the peeling chrome). I also test drove a base model Escalade with 18s while shopping and the difference in comfort was night and day.