We have around 10 implementations with FTD. I can tell you will give you a little pain in the head because there is some features that you need to work hard to delivery everything like customers want.
SSL/TLS decryption is the most trick feature imo. There is no many options to make a exception ( you can not add a external feed list to exclude. ex: office 365 ). You only can use URL categories and others SSL/TLS options to do this and, imo, is not the best way to to this.
FMC 184.108.40.206 is too slow if you comper if others vendor. But is much better now.
I like ASA a lot, working with Firepower about a 2 years need much improve to beat firewalls solutions like paloalto and fortnet. ( its sad but its true )
Btw all implementations was sucessfull. If you need some help we can help you.
Thanks for answer.
What about VPN functionalities. Both S2S VPN and AnyConnect Remote Access (group polices, Dynamic Access Polices, XML profiles)?
FTD now supports S2S VPN and RA VPN.
I have also deployed multiple FTDs for multiple customers in production. I have done many S2S VPNs. I have labbed up the AnyConnect RA VPN, as well.
I don't believe Dynamic Access Policies are supported at this time. But, depending on what you're using it for, you may have other options.
If you have specific use cases you want to confirm are available, you probably want to chat with your partner/account team.
in the anyconnect the FTD have some limitations
Currently unsupported on FTD, but available on ASA:
you can check this guide
I have been on a project for the past few months deploying ASA5516s converted to FTDs. The conversion takes about 3 hours. The FTDs are configured in a HA pair with no issues so far. The routing protocol is EIGRP so I had to use Flexconfig. Flexconfig takes a little time to get used to and it has been good. We had an issue with EIGRP authentication and Cisco has released a patch to us to take care of that issue.
With FTDs you do give up CLI configuration and that can slow down the configuration process, especially with the HA pair.