Well, technically, the 195-60R14's are the optional size for the A3s. 185-60R14 is what the A3s are equipped with from factory. So, you were running with a slightly off RPM anyhow. I am running the 195's right now, the odometer is off by ~2%, but the spedometer is pretty much on (by default, the spedometer in VWs show slightly faster than what you are actually travelling) Now, with the 15" rims, you have been travelling an extra % faster...so your odometer will be off again. Now you want to go even bigger?
Anyhow, in terms of fitting, go out to your car, and measure an extra 2" outside of your current tire. Diameter is an extra 2", radius (measured from center) is about 1" off. If you measure up and can accomodate the extra size, then it should be okay...just don't understand why you don't want to go with something closer to OEM. I have no idea if this tire size exists, but if you want to be as close to OEM as possible, you might look at 195-50R15s. Only 0.3% off.