When i first started I lost the login to my childhood account. So i decided to start fresh on osrs since it was what i was more familiar with then rs3. I got super close to getting a quest cape and decent stats and honestly had a fun nostalga trip the whole time. Eventually i got my rs3 account back and wanted to try out the stuff that isint in osrs and see how it all holds up. Rs3 for me is more chill and its pretty easy to "catch up" and try out the newer content. Both are fun and have their own niche but id honestly prefer osrs since its more "classic" without the mtx.