I am aware the Z06 is not a convertible - there are many modified convertible C5's andC6' around these parts that are still cheaper and more powerful and consist of ore mature packages than this one.
You would still be better off importing a modified car - it will be cheaper and faster and better made.
How many cars do you think Geiger make a year? Local tuners modify hundreds each year.
The fact that they sell"a lowering kit" is already warning sign that these Geiger folks may not be your best choice for Corvette tuning
The Corvette is able to be lowered just by fidling with the suspension - no need for a kit, unless you need the spanner and a picture to show you what bolts to twist..
The same way Alpina and Schnitzer know BMW, there are other tuners that know Corvette far better than these guys.
I am guessing that their packages are all rebranded LPE parts anyway.