I highly suggest you get a "GO room" because they are newer in comparison. Thumbs up for being pet friendly as well! You can get discounted rates if you and your guest are Total Rewards members. That goes for any property listed under the Total Rewards card!
Yes, Flamingo is an older hotel, but for it's location on the strip + cost = not terrible. I opt to gamble at the casinos nearby anyway. I've personally never had a bad experience with the front desk, security or customer service.