Which VPN Clients can I use with my license (XG210)

I am a Check Point / Cisco and Fortinet Firewall engineer and hence I am familiar with Firewalls.....

I wish to set up remote access using a VPN client (a thick client). However after reading the "Sophos-XG-Firewall-Administrator-Guide.pdf" I am unsure which VPN clients I am licensed to use.

The hardware is XG210 running (SFOS 15.01.0) and it is licensed for the following features:

Base Firewall
Network Protection
Web Protection
Email Protection
Web Server Protection
Enhanced Support

I understand I need to purchase additional licenses for the "Sophos IPSEC Client" if I wish to use this client. I haven't purchased these IPSEC Client licenses so I want to look at other options.

In summary I have the following questions:

1. Can I use the "Cisco VPN Client" for up to 25 users with my existing license?
2. Can I use an SSL VPN client (such as OpenVPN) for up to 25 users with my existing license?
3. Can I download a trial version of the "Sophos IPSEC Client" to test it before buying?

The users laptops are running Windows 7.

Many thanks

Damien