This post is for compiling all modems added by others to this thread in one place. I will work backwards through the thread and get them all added to this post, giving credit to the original poster of course.
All modems are for the 9100 model unless otherwise specified.
VEYKA'S MODEM COLLECTION (CWM flashable) (thanks to veyka):
The name of the Modem usually specifies the region its intended for, however... this doesn't mean it will work best for you. Classification of the Modem regions is as follows:
CE---> Belgium, Luxembourg, Netherlands
DX---> Indonesia, Malaysia, Philippines, Singapore, Vietnam
DZ---> Malaysia, Singapore
JA---> South Africa
JC---> Algeria, Morocco, Nigeria, South Africa, Tunisia
JP---> Arabic, Algeria, Egypt, Iran, Iraq, Kuwait, Morocco, Nigeria, Oman, Pakistan, Saudi Arabia, Syria
JV---> Tunisia, Turkey
UG---> North America
UH---> Latin America, The Caribbean
XE---> Bulgaria, Estonia, Kazakhstan, Latvia, Lithuania, Russia, Ukraine
XX---> Austria, Belgium, France, Germany, Hungary, United Kingdom
XW---> Austria, Belgium, France, Germany, Hungary, Italy, Nordic, Spain, United Kingdom
ZC---> China, Hong Kong
ZH---> Hong Kong
ZS---> China, Hong Kong
BVLP7 (tested by many, deemed to be a fantastic modem)
*Modem/Radio/Baseband is all the same thing and can be seen by going to Settings - About Phone - Baseband. It's basically a driver which receives and sends Mobile Network signals as well as handling switching between GPRS, 3G, HSDPA etc....... (but not WiFi connection, that and switchover between Mobile Network and WiFi is handled by the kernel). Reasoning as to why Modem has no influence on WiFi can be found in this post by Entropy - http://forum.xda-developers.com/show...postcount=6556
*There is no one "Best" modem for everybody. Unfortunately you actually have to try to find the modem which works perfectly for you on performance, strength and battery drain levels. The good thing is that from my lengthy 8 month experience with Galaxy S2, I'm happy to report that there are a few modems that seem to perform well geographically for most users. These modems are KE7, KH3, KI3, KI4, KL1, LPS, NEKF2, NELP2 & NELP3.
*Modems do not need to be matched up with firmware like it's done with ROMs and Kernels. For example, a KI4 modem can be used with a KL1 ROM and the other way round. The only thing you need to pay attention to is what model your SGS2 is. 9100 and 9100 modems are compatible across both models. However, 9100 model and US variants are not cross compatible since the devices are designed to work on different bands.
*I will add a flashing guide to post number 5 soon, hence why it says "Work in progress.....". For the moment I suggest asking Mr. Google to do a search for you. Bottom line is, for CWM packaged modems you need to be rooted and have a working CWM recovery (flash the CWM modem zip within recovery). For .TAR packages, all you need to do is flash it while your device is in Download Mode and connected to ODIN. The .TAR file should be selected in the PHONE field. Don't touch anything else.
*Usually just flashing and then using the same modem for 3-5 days should tell you how well it performs in your are and with you Mobile Network operator. Please remember that it takes around 2-3 days for a Modem to "settle" and achieve optimum performance, so don't judge how good a Modem is straight after flashing. That's where a lot of people fail when asserting battery drain.
Looking forward to see this updated maybe collect feedback from users regarding reception and power usage etc and from what area in the world. And if possible a short summery for them to after feedback.
Earlier today, we commended Motorola on its efforts to work with the … more
XDA Developers was founded by developers, for developers. It is now a valuable resource for people who want to make the most of their mobile devices, from customizing the look and feel to adding new functionality. Are you a developer?