What do you like best about the product?

Easy to understand sustem
Ability to create as many one off or use specific cards as needed
Predictible credit limit
The support team is very helpful and can be reached via chat or phone as needed.

What do you dislike about the product?

Brex requires that you keep a balance of $10k in linked bank accounts to maintan a credit limit of $5k, to use more you have to prepay.
It takes time with a linked balance over $25k to get a higher credit limit, or time to show activity.
If you need to top up to cover expenses you can do a prepay (as above) or an auto prepay. Prepay can be the full outstanding balance or an amount that you set, but the auto prepay is only the full amount. This means you can't just automatically top up $1k until the end of the month to cover services that hit at different times of the month.

What problems is the product solving and how is that benefiting you?

Brex was our first corporate card, enabling us to subscribe to cloud services and run the business.
The ability for expense/budget / vendor speffic cards is great, and lets you create a physical one for things like travel gas with limits (prevents them scamming you).