Another classic vegas Gem! I love Frankies, but man will the drinks mess you up.
I had the one drink without rum, and I do not recommend it because it tasted like Robotusen, however I chased it with another drink, which left me on my ass. The drinks are good price $20 with a (nice) tiki glass and $9 otherwise. It has a skull rating, so I suggest you pay attention, if you don't' want to get drunk.
Frankies is laid back, and pure tiki. Two larger seating areas int eh back which are good for groups and then smaller tables as well. The chairs at the small tables are not comfortable, but very tiki.
The vibe is laid back, and has a Jon Waters feel to it.