We just stayed at this exact hotel two weeks ago & used ART for 2 out of our 3 days & it worked out pretty well for us.
I would say that if you were trying to make a early Magic Morning at
Disneyland that starts at 7am you probably won’t make it for rope drop at the start. It’s supposed to start picking up an hour & 45 mins before regular park opening which is 6:15am but on our last day which was a Saturday(also an MM early day but we used ours earlier on our trip on Thursday)the ART didn’t show up at 6:15 at all & so when we were there for pickup at 6:45 the bus was pretty full after our stop but luckily it was the only one so we had no problems getting on. Basically I would Uber/Lyft if you want/need to be theee very early for MM otherwise ART works great! You do have to fold your strollers & at night the #12 bus route can get really, really full after fireworks/WOC shows. The bus drivers really cram everyone in! Let me know if you have other questions!