I've personally never met a radiologist that was unhappy with their choice of specialty. I'm sure they exist, but overall they appear to be a satisfied group, probably above average in the combination of compensation, time off/vacation, and overall job satisfaction. If you've done electives in it and weighed the pros and cons (which you clearly have), then trust your judgment and rest easy that chances are your concerns may dissipate once you start training. In the worst case scenario, transferring out is also doable.