I would drive it for another week and see if it consistently loses the same amount of oil. If it is not dripping oil, then it is eating it. It could be slipping past the piston rings or valve stem seals. Both have been modified, so we can't assume either was done correctly. If they did not install the oil control rings correctly (lowest groove on piston), then you will burn oil and leave a pretty consistent smoke behind you. It can be light enough that you won't notice it yourself. You need someone to follow you. This happened to me on my first build. The piston company forgot to include a support that went below the oil control rings (pistons had the pin moved up high enough that it cut into the lower groove for oil control rings). I installed the standard three oil control rings, but the lack of support let them move around and leak. Installing the support fixed the problem. If there is an issue with the valve stem seals, I believe that vacuum in the intake manifold at idle will draw oil in from the head. You'll leave a cloud of smoke as soon as you accelerate away from idle, but it will clear as you load the engine up. I have not experienced this myself. Again, it helps if someone follows you. Check that out and then do a compression test. If you find one cylinder way low, you will have something to focus on.

Corbin
'97 GSX dressed like a '95 ESi