Sounds like an idea. How the RAM speed will affect performance depends on what program you use and stuff like that,
but according to Anandtech's testing with DDR3 on Haswell, there are some gains to be had. They ran tests with a video converter program and H.264 encoding, RAM speeds above 1866MHz were able to get a 5~6% improvement over 1333/1600MHz RAM.
Well,
2x8GB kits of 1600MHz start at $58 and
same size kits of 2133MHz start at ~$70. The
G.Skill Sniper kit at $70 is a decent price, but the RAM's heatsink design is rather large and may interfere with a large CPU cooler if yours happens to be wide enough to possibly interfere with the RAM slots. Otherwise go with the
G.Skill Ares kit for $75, that's a smaller design that should fit under most large CPU coolers easily.
Sorry for the lack of help, but few of us order from prebuilt gaming PC companies so we're not too familiar with how much they tend to charge. Alternatively, consider ordering a list of parts from NCIXUS along with
the assembly option. For $50 they'll put it together, test it, install OS if you also order it from them, and they'll give you one year warranty on the complete PC as well as all of the packaging and accessories from the parts you chose so you have it in case you need manuals, extra parts, or something breaks down (graphics card, PSU, etc) and you just want to contact the manufacturer to send back that one part for warranty purposes.
In case no one takes you up on your offer, there's also the
"FREE to a good home" thread, someone there might also appreciate it.
