I have a couple of questions regarding recommendation letters.
1) Does the status of the letter writer matter greatly to admission committees? For example, I have done research with a full professor, an assistant professor and a lecturer in my department. If the three of them write me a letter, does that automatically put me at a disadvantage because two of them are not full professors or one of them is a lecturer?
2) Should I bother asking for a letter from professors that only know me through classes? I have a potential fourth person in mind - he is a professor I took two classes with and did well in both. I have a feeling the people I've done research under would be much better suited to write me a strong recommendation letter. In my understanding, "so-and-so was a good student in my X and Y class" will probably impress no-one, even if it comes from an established professor.
Thanks in advance for any responses.