Two things to watch out for:

1) Montanita is a growing tourist destination. You need to resist the temptation to spend all your time outside the classroom speaking English with other tourists. You're not going to learn much Spanish if you do that.

2) The accent spoken on Ecuador's coast isn't the easiest to understand for a beginner. They speak rapidly and tend to clip the S sound the end of words or if it's followed by a consonant. "Habla usted español?" often becomes "Habla uh-ted eh-pañol?" You'll get the proper accent in the classroom. Out of the street, you might hear something different.

Thanks for the reply Jeff. I'm going to be very dedicated wherever im studying and will only be using spanish no matter how frusterating it becomes. I never realized about the different accents. I heard Ecuador had a easy to understand accent but I guess it varys from region to region. Would you recommend i dont study spanish on the coast then?

The "standard" Spanish accent in Ecuador is spoken in the highlands. I think you just have to listen a little more closely on the coast. That's all. If the surfing is important to you, Montanita is the place to be.

Well spanish is firstly important and surfing is second

Why not consider first studying a week or so in Quito, which is a fascinating city in my opinion and then travel on to Montañitos, which is as the others comment here THE surfspot in Ecuador. I was really impressed how much I learned in just 2 weeks time and it made my travel so much more fun. I booked through studyspanishlatinamerica.com and they also have a school in Montañitos I believe where you get to stay in really cool cabañas. Check it out and have fun surfing!

Definitely go and check out Quito, for learning spanish or not, there is so much to see and do. I just read this article on this blog page volunteerinsouthamericablog.org which gives you an impression, and from here it's only a 30 mins. flight to Guayaquil and then a beautiful 2.5 hours busride to the beach of Montañitos. If you only have 3 months I would try to see as much as possible!

I would check out Otra Ola http://www.otraola.com, they are a Spanish, Surf and Yoga school in Ayampe.

I really loved Canoa, few Km north of Montañitas. It's really beautiful small village, not so crowdy with an amazing beach to surf. No school but lot of surfer guys you can speak with. At least is worth a day trip.

The most important thing is to speak speak speak with other Spanish speakers and don't fall into the tourist trap of spending too much time with people who speak your native tongue.

My advice? Jump-start learning Spanish before you leave- you'll use it when you get there. www.spanishexito.com has a cool little course that is a great intro and pretty cheap.