Well that depends. Any sectors pending reallocation is not good. But it's ok as long as there not thausands of them and they do not increase over time. So what you should do it to run a few more times the preclear script and check if there will be an increase in "5 Reallocated_Sector_Ct " and the pending sectors. After you run the next preclear, the 17 pending sectors should have been reallocated and appear in "5 Reallocated_Sector_Ct ".
If there is no increase in pending sectors, you'll probably be fine. Just keep an eye on it from time to time by running some SMART tests while it's in use in your array.