While being somehow dated as it was introduced back in 2015, it received some midlife updates and still holds up with the current models, at least in smaller dimensions. At the right price, it could be a great choice.
255/60 R17 doesn't belong to the most popular dimensions for winter tyres - there are 22 tyre models available, which can be compared to 175/70 R14, 165/65 R13, 165/70 R13. Let's break down the sizing - 60 is height of the tyre, which is calculated as 60% of the tyre width (255mm), which means the sidewall height has 153 mm. The wheel diameter is R17, which means it fits to a 17 inch/431.8mm diameter wheel. The total circumference of the tyre is 2317.87 mm, which is very similar to 255/65 R16(2318.18 mm), 255/55 R18(2317.55 mm), 255/50 R19(2317.24 mm), 255/70 R15(2318.5 mm), 255/45 R20(2316.92 mm), 255/40 R21(2316.61 mm), 235/65 R17(2316.3 mm). There are multiple speed indexes available for winter tyres in 255/60 R17: H(210km/h), Q(160km/h), S(180km/h), V(240km/h). The same goes for weight indexes: 106, 110.