Go with the JG MP5. It will have much better internal quality then the Broxa. The Broxa is an overpriced clearsoft gun. Yes it is a good project gun, but if you're looking for something to start you into the sport, buy the JG if that is all you can afford.
I started with a Firepower XM8, bought an Echo 1 G36 gearbox, put a TM G36 hop up in, and a Madbull Tightbore... Wasn't a fun experience. Yes I knew my gun, but I also spent alot of time and money ordering parts and waiting for them to arrive and installing them.
The JG MP5 series should suit your needs well.
I still recommend getting AV'd and checking out the classifieds before you buy it though.
KJW Mk18 MOD1 BLOCK 2 - Well VSR-10 - Les Baer Ultimate Recon