For a $100 premium, I wouldn't hesitate to book on TK (so long as both the BOMIST and ISTYYZ flights have that cabin). Comfort Class is a fantastic value, which is probably why it's being phased out.
I flew it ISTHKG earlier this year and got a decent night's sleep, and the cabin was fairly empty with the adjacent seat open. The seats somewhat resemble the old barcalounger seats on UA or DL, but pitch isn't quite as generous (but definitely more than Y+ on UA). I found the food to be mediocre, but it was definitely a step (or two) above catering in Y on TK or UA; for airplane food, it exceeded my expectations.
Not needing to clear the US border (or transit EWR) is another plus to consider when taking TK.