As per other members in this forum
"Arguing on the Internet is like competing in the special olympics. Win or lose, you're still retarded".

The following are facts.

1) R12 is banned and not manufactured by all countries in the world.
2) R12 is OZONE depleting and contributes to global warming.
3) You cannot buy R12 without a EPA license. How easy to get a EPA license is procedural loophole and should be discounted.
4) R134a is comparable to R12 as per the scientific paper.
Executive summary:
"The results indicate that the performance of R134a is very similar to that of R12 justifying the claim that it is a drop in replacement for R12"
http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6V1Y-48S3121-1&_user=10&_rdoc=1&_fmt=&_orig=search&_sort=d&view=c&_acct=C000050221&_version=1&_urlVersion=0&_userid=10&md5=dfc8561b2249d18febba87a87cec6124
5) Conversion kits readily available from most Autoshops and I am very happy with my conversion(s).

__________________
Not MBZ nor A/C trained professional but a die-hard DIY and green engineer. Use the info at your own peril. Picked up 2 Infractions because of disagreements. NOW reversed.

W124 Keyless remote, PM for details. http://www.peachparts.com/shopforum/mercedes-used-parts-sale-wanted/334620-fs-w124-chasis-keyless-remote-%2450-shipped.html

1 X 2006 CDI
1 x 87 300SDL
1 x 87 300D
1 x 87 300TDT wagon
1 x 83 300D
1 x 84 190D ( 5 sp ) - All R134 converted + keyless entry.