Figured out how to run that disktester thing...
Code:
disktester rs -t 4G -i 20 Macintosh\ HD
------------- Averages for "Macintosh HD" (4GB/4MB, 20 iterations) -------------
Iteration Write MB/sec Read MB/sec
1 427 515
2 434 505
3 430 509
4 432 507
5 428 508
6 436 511
7 426 507
8 432 508
9 431 505
10 426 508
11 426 509
12 428 507
13 429 509
14 425 506
15 428 508
16 427 507
17 427 505
18 430 507
19 425 504
20 428 509
Slowest 425 504
Fastest 436 515
Average 429 508
Median 428 508
Range 10.7 10.2
Command "run-sequential" executed in 361.19 seconds on Monday, April 18
I was even doing a background iTunes update while that was running too.