Have LR3 and PS 5.5 . Lightroom can do most of my image editing, the interface is a restylized version of Adobe Camera Raw. When it comes to printing, I prefer PS as my printer has a plug-in and the softproofing helps me to avoid out-of-gamut surprises. Overall, I use LR3 far more than DPP or PS5. It has extended capabilities compared to DPP, but I do use the 'Edit in PS' feature for perspective corrections (keystoning), better selection of sharpening methods for highly pushed images, and printing. DPP gets more usage at work where I tend to use a tethered camera a lot for macro shots before and after testing material samples. At the end of the day, if I could only keep one of the three at home it would be LR3. The library function and the developing interface make it more user-friendly than PS could ever be, though I would on occasion miss the larger feature set of PS.

Given that you are scripting in Matlab, presumably using toolbox functions, you may find that the ability to create scripts in PS5.5 for automating repetitive processing tasks is to your liking. Don't suppose your workplace could use the upgrade for image processing before data analysis and would allow you use of the license for when you work at home? I know you work in a lab environment. If it is part of an educational institution be aware that there are academic discounts from Adobe for students, staff and faculty to purchase for personal usage.