I've been shopping for a CTS-V3 the past 2 months and have a question about the coolant reservoir. I've probably looked at ten V3's and sometimes the reservoir is full, sometimes half empty or sometimes the coolant is more orange (rust?). Is there any warning signs I should be looking for? Is it ok if the reservoir is not totally full, or the coolant is more orange than pink? This is the reservoir that also feeds from the supercharger I assume? Thanks in advance.