Yes, hotel wifi is a great way to extend your 300mb roaming allowance.
do you plan to stay the entire trip in hotel for wifi? Many use Roam Mobility with a SIM card swap or on a second phone to maximize my roaming allowance in most US States. http://www.roammobility.com/talk-text-data
how fast is that hotel wifi? how fast is it in the evening when everyone else is using wifi after dinner? I connect to this site to see if it's about 2Mbps for video. Otherwise, limit myself to just emails. Wifi speeds improve in the morning and mid-day. Also experiment with wifi in the bathroom.... I discovered the wifi works 4 times faster when I'm closer to the hallway in some hotels instead of the window desk as the repeaters are in the halls. http://rimouski.speedtest.telus.com/
hotel wifi is unsecured.... consider a VPN to prevent data eavesdropping on your userid's and passwords.
is this hotel an online booking... do include the wifi speeds in your hotel review to help others.