That being said it would appear that Plextor's "S" or standard drive is typically a little weak in benches compared to similar models, though I suspect some SSD makers have figured out how to tweak their firmware to get false performance in benches, just as graphics card makers discovered. IMO Plextor should make the "Pro" models their base models and develop a truly better SSD if they are going to give it such a "Pro" title. The current Pro models should be priced at the "S" model prices.
In regards to Plextor's SSD quality, we simply have no clue how good they are or are not. With SSD makers releasing a new model SSD almost every couple months, SSD tech as Anandtech has stated: "Is very immature technology" and it shows with all of the firmware, data loss, RMAs, etc. associated with SSDs.
A 5 year warranty doesn't mean that the drive is built any better than a SSD with a 1 year warranty. The additional cost of a Plextor drive pays for the extended warranty, so you aren't getting anything for free and certainly no guarantee of more reliability. While it might be better, it may not. We won't know for another 3-5 years unless they all go bad sooner.
Before some folks have a knee-jerk reaction thinking that I am bashing Plextor, I am not. I have owned Plextor optical drives over the years and they were fine though they used a proprietary system which did not always make them widely compatible. Plextor SSDs may in fact turn out to be reliable SSDs, but we'll need to wait and see. With a new SSD model every few months I suspect that most SSD purchasers will be upgrading 7-10 model designs over the next 2 years so a 5 year warranty don't really mean much, even if you were not paying for it up front.
It would be nice to see Plextor set itself above and ahead of the competition by delivering a truly high reliability and quality consumer grade SSD at a fair price. Only time will tell if they can deliver.
For now, anyone looking to move to an SSD should carefully research all aspects of SSD compatibility and reliability because the situation is far from pretty and data loss, firmware updates, RMAs, reduced drive capacity, etc. is very common.