If you'd still like another opinion, I personally did/do both.
Biology, while you do have to understand everything too, it is more memory work. It's much more denser in terms of workload and information (plenty of reading and writing) whereas Chemistry is more analytical with calculations.
Neither are easy, it's just what you're more suited to I feel because both do have their own perks. If you're better at comprehending large slabs of words, remembering and working out relationships then Biology is for you. If you're better at say, Maths with understanding numbers and abstract concepts you'll do fine. That said, I can cope with 3U Maths but, I can't grasp vague concepts such as the mole or what the entire point of them is so, I've dropped Chem.
Most people who were in my Chemistry class were Maths-oriented whereas those in my Biology class are more Humanities/English-based.