If it's enough or not depends on what you intend to put on it, same as if it was a HDD. As for performance improvement, it's quite high but smaller SSDs are slower than larger counterparts. Combining smaller SSD with a larger HDD is the way to go. Higher performance of SSD and lower price/GB for other uses like personal files and non essential programs is cheapest combination. Actual formatted capacity is about 111GB.
Count on at least 20GB for W10 (without Hibernation file, hyberfill,sys, restore points and large virtual memory), about 10GB free for proper operation of windows and a gig or two for other stuff.