Many users of HFS have asked in the past (on this forum), what is the best alternative to DynDNS, and from my own experience, nothing beats FreeDNS.afraid.org(and this is NOT an advertisement, since I'm not getting paid for commenting this).
His owner (Joshua Anderson) is very friendly, and his services are trustworthy (he has more than 20 years of experience, working online since 2001).
You can use it for free or by paying only $5 USD/monthly ($60/yr). Although I'm not a Premium member of them (since I currently can't afford it), I highly recommend it to anyone here, and I can't say enough good things about this service.
You can use your own domain (to delegate your DNS to them) and start using it to self-host content (for example, using HFS as server); or by choosing a subdomain from any of their 41,950 domains, which half of them, are only available if you are a paid customer (by getting a Premium Membership). But if your budget is tight, you can use a subdomain, and start using it for free, for as long as you want.If you need any help to configure and use it with HFS, just leave a message here, and I will try my best to help you.
Cheers,
Leo.-