Sorry, only just now seeing all the questions about tiff.
There is ZERO difference in the quality of a tiff vs a psd. They are both layered files, you create and work and edit in the exact same way as a psd. The only difference is the ridiculous amount of space you will save by going tiff vs psd, and your LO's will say .tiff at the end instead
Here's a link to a thread where it was discussed. I link up to an article explaining that it's a lossless conversion, and I posted the settings for saving as a tiff.
All my templates have been converted to tiff, and now I only work with tiff files.
PS~Beckie, get yourself an EHD! I have a large HD on my laptop, but I keep all my scrap supplies, and all my photos on my EHD's (I have 3, lol.) to keep the HD clean and things running smooth.