You haven't linked to any kit?
An AIO is good, but a decent air cooler will be just as good. A custom loop has the advantage of being...
- Fun to build
- Better at cooling your kit
- Adaptable should you add or remove kit
- Awesome looking when built with patience and forethought
A custom loop has the following disadvantages...
- Much more expensive than an AIO or air cooler
- Requires maintenance every 6 months to a year
- May leak and cause damage if you don't build with care (unlikely, but not impossible)
HTH