if i have to i would pick the IOST as its cheaper right now, collateral wouldn't cost much for it compare to those expensive tokens already.
Solid staking coin with multiple privacy features (including ring sigs, stealth addresses, integrated Tor+obfs4), declining inflation, decent exchange options, and smart developers working on more wallet options and privacy improvements for the roadmap. Also easy to setup and keep updated for staking on a raspberry pi.
XSPEC is a great coin, price started i believe was about 0.02USD and still holding on today to more than $0.30. were they the first to introduce that Proof-of-Anonymous-Stake? not sure what it really meant though but even with DASH and few others, there is no mandatory to submit documents to stake coins.