spazz out or not?

Tuesday:
10am-chem lab(30797)
chem lab
chem lab
chem 230(30796)
biosci203
3pm- foodsci201

Wed:
chem lab(30798)(alternative)
chem lab(alt)
chem lab(alt)
chem 230
biosci 203 lab(even)
biosci203 lab(even)
biosci203 lab(even)

Thurs:
foodsci lab(30677)
foodsci lab
foodsci lab
chem 230
biosci203
foodsci201

that's my timetable for sem 2 at the moment. on tuesdays and thursdays i have 6 hours in a row. 3 hour lab+3 one hour lectures. now, notice on wednesday i've written chem lab(alternative). it's a stream which i can change to.. and if i do change to that stream.. then i'll be having 3 hour lab, 1 hour lecture and then another 3 hour lab. but then the 2nd 3 hour lab is only on alternate weeks.. so, every other week i only have 3 hour lab and an hour lecture. i'm now trying to decide which is a better alternative.. wonder which is better...any comments anyone?