Well, I'm an electrician and I use too change jobs whenever the money was better. I traveled around the country, doing huge projects. When they were done I would then look for the next highest paying job. I made a lot of money, I made $35,000 in 6 months once. Then it caught up with me. I had a long resume of former employers. Almost all, I left on good terms. When I tried to get a new job the interviewer would look at all the times I changed jobs, and would ask why I couldn't keep a job for more than 6 or 7 months. No matter what I had to say it was always a strike against me.
I settled down found a job wiring houses, which I hate, because after nuclear power plants, slaughter houses, steal mills, ect houses were pretty boring. The company I was working for was small and the owners was very good to me. I got 3 $1 raises within 9 months. When I got married, they gave me a bonus check for $500. During the Christmas party the owners bragged about me and another guy, and told us how good and dependable workers we were.
While I was working there I got a call from a guy that I use to work for, he told me he had a job a few miles from my house and offered me $7 more dollars than I was making at the time. I told him I liked the guys I was working for and I can't just leave them.
Less than a month after the Christmas party me and the other guy that they bragged on so much was called into the office. We were told that we couldn't do our job and we were both fired. It turned out that two guys applied for jobs and said they would work for $2 less than we were making.
So in the end you have to do whatever is best for you. I agree that you need to get more experience, that is your best asset. If I were you I would apply with the other company and see what they have to offer. If it's a better deal take it. You can gain way more experience if you're working 40 hrs a week instead of 20.