First, chastising everyone in your status for not replying instantly ain't a great way to win friends and influence people . . .
just sayin . . .
Moving past that, PRS+ is very stable for the '350, short of a few known bugs. The current known bugs are listed on the
project page.
The latest OEM ROM (1.0.00.14080) will NOT allow PRS+ to flash. I haven't heard anything about when it'll be fixed.
Assuming you can, the loading process is fairly painless. Changing out the roms is at a hobbyist level, but not by much, anymore.
If you do load it, most of the new features melt into the background. The modifications are built onto the OEM rom, so out of the box it performs almost the same. the only big default differences are the clock in the bottom corner appears and the Periodicals-Collections-Notes row gets swapped out (I think the default is "folders-collections-more", but I've changed them and forgot what they were). The "More" section contains the games and calculator.
Long story short, if you feel the OEM rom is suitable for you kids, PRS+ will do nicely.
If you don't like it, the new rom can be loaded over PRS+, or you can get the old roms from the "
russified" CFWs -- loading these is a bit more work, but the translated instructions do work.