Is the repeated use of units in sentence okay?
The answer will depend on your style guide. A Style guide that I am familiar with, the American Physical Society Style manual, says,
Do not repeat units of measure in a series of 2 or more items, in a range of values, with a ± symbol, with the combinations "from...to" and "between...and", with versus (vs.), or with a multiplication (×) symbol. However, when other words intervene, units can be repeated if necessary for clarity.
So your first option looks right to me.