Superb City and it is the Capital of that region. Friendly, Rich in Culture, summer temperature around 26 to 44 degrees. Great Rail Links to mainland Astana and Almatty. Also to Chelyabinsk in Russia.
Very safe place, very friendly people, many tourist attractions such as the central park and the many Cafes around town. Very inexpensive, and eating out is always good value for money. On average a good Cafe / Restaurant will cost around $5 / $7 dollars per head, and the food and service are very good in most places.
Great swimming baths, and good fishing just outside of town. Visit the many banjas (saunas) it is a great experience, and not seedy like here in the West. I can only say this, do yourself a favour and visit Kostanai, rich in culture, safety and people. You will not be disappointed.