Linktube is one of the awesome link-in bio tool I've ever discovered.
With enthusiasm, I bought the deal with 'Agency Plan' and after using it for 6 months now my clients are pissed at me!!! I've created Smart pages for my clients and now their SSL certificated are expired :(

PROS :
+ Excellent functionality with lots of instant customisation,
+ All social media can be linked to a single page,
+ Dynamic RSS feeds which automatically updates itself,
+ Custom domain & white label adds the 100% ownership of Smartpage owner.

CONS :
- Expired SSL Certificates do not get renewed even after 2 months (bad impression),
- Linktube.com downtime is uncertain and not even communicated prior,
- No support from owner Sanket, Carl, or support staff at all.
- They don't answer any support tickets at all.

Overall, Linktube is an excellent product with no future roadmap of new features to be added and lags support if something breaks. If the support from the Linktube gets improved then this is worth every penny. I'll update my review time-to-time..