Be less specific about memory usage predictions
diff --git a/include/mbedtls/config.h b/include/mbedtls/config.h
index 37a9d07..94e3efb 100644
--- a/include/mbedtls/config.h
+++ b/include/mbedtls/config.h
@@ -387,8 +387,8 @@
* Comment this macro to generate AES tables in RAM at runtime.
*
* Tradeoff: Using precomputed ROM tables reduces the time to setup
- * an AES context but comes at the cost of additional 8192b ROM use
- * (resp. 2048b if \c MBEDTLS_AES_FEWER_TABLES below is used).
+ * an AES context but comes at the cost of additional ~8kb ROM use
+ * (resp. ~2kb if \c MBEDTLS_AES_FEWER_TABLES below is used).
*
* This option is independent of \c MBEDTLS_AES_FEWER_TABLES.
*
@@ -406,7 +406,7 @@
* (the tables are entry-wise rotations of one another).
*
* Tradeoff: Uncommenting this reduces the RAM / ROM footprint
- * by 6144b but at the cost of more arithmetic operations during
+ * by ~6kb but at the cost of more arithmetic operations during
* runtime. Specifically, one has to compare 4 accesses within
* different tables to 4 accesses with additional arithmetic
* operations within the same table. The performance gain/loss