You have a an excellent Samsung 830 Series SATA 3 6Gb/s 128GB Solid State Drive. Samsung has a stellar track record. I do not recommend upgrading at this time unless you need more capacity. If you are on a tight budget have you considered a large capacity hard disk drive to store data files?
The ADATA ssd's are okay but they use an older SandForce SF-2281 Controller. SandForce hasn't come out with any new controllers in over 2 years. The current trend is to not purchase ssd's with SandForce controllers.
I maintain the ssd database listed in the sticky at the very top of this forum section. Here is the link:
http://www.johnnylucky.org/data-storage/ssd-database.html
Scroll down to the brands and models you are interested in and follow the links to the technical reviews.
I would disagree with your last coment. The 840 Pro and 840 Series ssd's are relaively new. They were released just 4 months ago. A few weeks ago newegg had a special promotion. The Samsung 840 PRO 256GB ssd was on sale for $199.99 and free shipping. The best place to check for special promotions and daily deals is over at Logic Buy. Here is a link to the ssd/hdd page:
http://www.logicbuy.com/categorydeals/computers/hard-drives-ssd
You just have to be patient and check twice a day - once in the morning and once in the afternnon. The daily deals can sell out fast.
BTW - Yesterday morning Samsung released SSD Magician Version 4.0. Samsung did an excellent job of upgrading the utility. There are some new features that are very user friendly.