+1 for saitek eclipse II. I also have said version and am quite happy with it. I like the classic keyboard layout; therefore, the saitek II did exactly as I needed and that was to glow in the dark. I also like that you can choose from three different colors and adjust the brightness level. I cannot really comment on the durability as I've had mine for only a few months. It does, however, have a nice weighty feel to it and feels/looks nicely constructed.
I think it does not worth it. I had it for years (the Eclipse one - one of the brightest as it goes), and it is not that easy to read in the dark. It is only marginally better than good keyboard with light only from the monitor. And if you have even a little additional ambient light, normal keyboard is easier to read.
On top of that, under normal light conditions, the normal keyboards are much better becasue the back-lighted keyboard has very poor contrast of the letters.
IMO, the only use of this keyboards is if you HAVE to work in absolute darkness, like with telescopes. But for gaming, the standard keyboards are better. It is, of course, just my opinion, your millage may vary.
Ive had the saitek eclipse 2 for a couple of years no problems with reliability, I passed it on to my 6 year old son when I got a G15, the saitek is standing up to little kids use well. The eclipse two is well lit from underneath the lighting shines through the letters making it VERY good in the dark
The G15 looks cool, Ive only use the additional G keys on occaisions. The maing game I planned on using them for I stopped playing shortly after I got the keyboard, but I had it doint some awesome stuff before I qui. The LCD display can be usefull for the performance monitor although thats been mostly replaced by using a second screen to display more information...
The G15 is a good keyboard, it has lots of "potential" but I just havent really got round to using that potential much yet, no fault of the keyboards there, but in reality the fact that I havent put the extra functions to much use suggests I could have spent my money better Still it isnt over till the fat lady sings, theres no saying I wont put the extras to great use at some point