I've just been using the Harvest Berries and Enjoy the Ride dies and stamps. For Enjoy the Ride, I cut the cars and then stamp them. You really do need to stand up because if you don't place the stamp exactly right, you miss getting the line across the top of the car. It's easier to be sure you are going to get that line when you look from directly above your work.
The Harvest Berries are difficult because the stems are really slender, whether you cut or stamp first. I was less frustrated when I cut before I stamped. I did more trimming of the die-cuts than I would like to have done, because the margins on the dies that are meant to go with certain stamps are wider than I like when fussy-cutting images. To get a BETTER look than the fussy-cut look is what I expect from a die, because my fussy-cutting looks like Grade One Art Project.
I love the PTI dies and impression plates, actually. My favorite die is the apple. I cut the apples using glossy red or green cardstock, then cut the stem and leaf part of matte green paper, trim it and glue it to the apple stem and leaf. A grid of these on black and white gingham is really cute.
My favorite impression plate is the plaid. It makes a perfect subtle background for masculine cards, especially.
Life before die-cutting and embossing......good thing we didn't realize how boring that was.

Stampaholism at work!
Bahb