[Bowers]

yeah im kinda in a good mood tonight..

First off here are a couple of reviews on jing gong products that i found here on asc while not specifically about the model you are inquiring about i think these should give you an idea about the companies quality in general

Jing gong mp5http://www.airsoftcanada.com/showthr...ight=jing+gong
jing gong ak47http://www.airsoftcanada.com/showthr...ight=jing+gong
Jing gong hk416http://www.airsoftcanada.com/showthr...ight=jing+gong
Jing gong m16a4http://www.airsoftcanada.com/showthr...ight=jing+gong

Now upon taking a trip over to the friendly neighborhood search engine and typing “Jing Gong M4 Review” I got the following results

courtesy of airsoft ohiohttp://www.airsoftohio.com/forums/sh...ad.php?t=18805
Courtesy of air soft faqshttp://www.airsoftfaqs.com/index2.ph...do_pdf=1&id=72
Courtesy of air soft forumhttp://www.airsoftforum.com/board/Ji...w-t109993.html

If reading isnt your thing there is always youtube granted there is a ton of god awful videos however the odd gem can be found from time to time

although this version is apparantly the "para" version which is a little different though it is a m4 varient by jing gong so you might get something useful from the video

YouTube - Jing Gong M4A1 Para Part 1 of 3

YouTube - Jing Gong M4A1 Para Part 2 of 3

YouTube - Jing Gong M4A1 Para Part 3 of 3

I hope this has helped you

cheers
bowers