Is there a huge difference in the more expensive HPS bulbs amd the regular???

I'm looking to buy a new light from htg supply and they are offering upgrade hps bulbs, the AgroMax and the SunMaster for a little bit more, is it worth it? Any body tried these out and noticed a difference?? Thanks!

the sunmaster is the best or so i hear as i use phillips. but go for the sunmaster if you can in both MH & HPS.

I appreciate it widowman! Something else strange I noticed is their less expensive "only hps" systems offer an additional MH conversion bulb alltogether less than just buying there mh/hps system. What the hell is that? is there any difference to ballasts in the systems?

often you get a "upgrade ballast" all products are cheap, but so are his prices. he does back it all with 1 year WARR