Yup. Most people's expansion difficulties are due to retarded pool configurations. If you accept that 1. disk is cheap and 2. mirrors, whilst expensive in terms of disk capacity are way better performance and more flexible, zfs rocks.
People seem to have it stuck in their head that bigger RAID numbers are better, but RAIDZ/RAIDZ2/RAIDZ3 are only really useful when you're dealing with HUGE numbers of disks and performance is not so important. Normally you're far better off creating a larger number of VDEV mirrors, both in terms of performance and in terms of flexibility.
Which brings up another point - those not used to dealing with enterprise storage may not realize that you can/should/maybe want an array with more than one RAID group in it. They end up putting all their disks in one big VDEV which sucks for performance and flexibility, then blame ZFS for not being flexible.
Read how it works, don't make retarded choices based on ignorance, and you'll be fine.