I have the LH-20A1S (non-LS SATA) and the SH-203B.
Honestly, I’ve had a bit more luck with the Lite-On. The SH-203B just doesn’t like my MCC04 media. It tries to overspeed it by default and fails. If I limit it to 16X, it works fine. The Lite-On doesn’t try to overspeed it by default, unless I turn overspeed on, then it tries to overspeed and fails but falls back at the end of the burn so it doesn’t make a crappy burn.
I just think the walking OPC is better on the LH-20A1S.
However, if you have any 20X-capable SL media, you want the 203B. This is because the Lite-On cannot do lossless linking at 20X. So if you get a buffer underrun during a 20X burn, you get a coaster. Honestly, this means you’re never really want to do a 20X burn on the Lite-On.
Also, if you ever plan on getting DVD+R DL media faster than 8X, you want the 203B, since it will write DVD+R DL media at up to 16X.
Also, there is region-free firmware for the Lite-On, but not for the 203B.
There, that’s all the data, you make up your own mind.