There’s already quite a bit of discussion of account aggregators in this thread although it’s been a while since it’s had any activity.
I’ve tried quite a few account aggregators. I’ve settled on Emma as the one I like most. The analytics and budgeting is similar to Monzo (but also encompassing my other accounts). I also like that it provides good transaction enrichment, unlike most other account aggregators. Its main limitation, I would say, is it doesn’t support as many banks and other financial institutions as other account aggregators.
I trust them because they are FCA authorised as an AISP.