I'm currently riding an older Trek 5500 (this was an early Lance bike). I am thinking of purchasing a new Cervelo R3 or RS. My current setup on the 52 cm Trek has the bars about 5-6 cm below the seat level. The stem has no rise (i.e., flat) and has about 3 cm of spacers between the top of the headset and base of the stem. The Trek head tube is 10 cm on the Trek. I'm curious if there are any of you out there who have had a Trek 5500 or 5200 and now have a Cervelo R3 or RS : HOW DOES THE FIT AND PERFORMANCE DIFFER??. This would help me a lot on my decision between the Cervelo R3 and RS , since I cannot be fit or test ride a new Cervelo where I live. Thanks in advance for your opinions.