My clinical year was at a mid-sized (~500-bed) hospital that had its own education program, so my 7 other classmates and I did supervised bench work starting at 0530, 600, 630, or 0700 until 1300 or 1400, then had a couple hours of class each day. I actually put in up to 20 hours per week beyond that working in the component room of the Blood Bank separating whole blood into pRBCs, FFP, and platelets. It was a long and sometimes stressful year!
While there isn't the same competition to get into MLS programs as there is for med school (thus some rocky grades are OK), the course work isn't slack. Undergrad courses in cell & molecular biology, microbiology, immunology, analytical chemistry, and instrumental analysis are the foundation of what you will be taught in an MLS program. You will also be dealing with basic statistic principles as they pertain to quality control.
Did you feel comfortable & interested in your undergrad labs? Did you do any research or work as a lab assistant where you got any hands on experience? How do you feel about working in a clinical setting where you have to interact with sick people and their families, or even have to draw their blood? Do you think you'd like to work with blood, urine, sputum, feces, and other body fluids? How do you feel about performing maintenance and troubleshooting errors on analyzers? These are some of the questions you should be asking.
As far as some observations about working in the field (at the same hospital I trained at)--
Pros: good (not great) pay out of undergrad, job security, use critical thinking skills to solve problems
Cons: work eve/night/weekends/holidays, interacting with nurses is difficult, "hidden" from patients (might be a pro for some), little respect, work tends to get repetitive
I left the lab for med school so that I could be more involved with the patient--rather than just providing info needed to treat, I want to know how that information fits with my patient and what to do with it.