With the current conversion rate that's around $92 USD. It's a fair buy - if you were to buy a refurbished Series 1 from Apple it would be about $189, although it would include a band and Apple Care for one year.
Battery life... before I upgraded, I could do about 28 hours between charges. That is without using any workout features and without using any particularly intensive Watch apps (mostly looking at news headlines and text messages once every few hours). But by hour 28 the Watch is down to the single percentage points of the battery. I did the same with my Series 1 as I do with my Series 4: charge it while showering each day (and then some), and no problems. The Series 4 has better battery life by a bit but I don't work 28 hour shifts anymore, so I'm not sure how it handles that "torture test."
Is it a good buy is another good question. If this is your first Watch and you're wanting to see if it's useful or not, I have mixed feelings. It took me a few months to find enough uses for my Watch to justify keeping it around and upgrading it; by the time the Series 4 rolled around, the Series 1 felt so slow that it was practically unbearable. If I were starting with the Watch today and started with a Series 1, I'm not sure that I would have kept going with the Watch. I'd probably recommend someone wanting to dip their toes in to start with a Series 3.
But you bought it already, so use it and enjoy it! Just know that if you get frustrated by some of the sluggishness, it's not an issue with the latest Watches.
