either will scratch, i had an all glass and major scratched the inside with a rock doing the magnet cleaning. no matter what you get you do have to be careful, granted glass is easier, but i am going for acrylic this time around.
i have had an acrylic wet/dry for about 10 years and its not yellow at all and i only see 1 scratch in it (that would be from moving and movers). some might say sumps dont get abused, but that is where all the action is going on. most dont care about their sumps scratching (i didnt) and it is fine.
this will however be my first acrylic aquarium.
gl with your choice (wait till you get to lighting lol)