I picked up some #150 main jets for my GS, but the jets I got have smaller heads on them than the stockers.  The diameter is probably 1 to 1.5mm less with the jets I have.  Is this an issue?  I can get different jets if I need to but if it doesn't make a difference I'll stick with the stuff I have now.

The hole is important not the size. In 2001+ bike like mine small round jets are used, but i bought some large round and they seem work fine.

The guy in the above post may have more experience on this, but I thought that the two different styles weren't interchangable. When I was ordering mine from the bike shop, they told me that they were different and I needed to find out what style I needed before I bought them. You could give it a shot, but it's kind of a hassle if you have to pull your carbs apart again to put the right ones in.

i brought some new jets last week and it was the same smaller head, but they worked fine, its as domas says the size of the hole that matters not the size of the head

Thanks, that's what I had figured, that the head style doesn't really matter as long as the hole size is correct.  The carbs are nearly ready to go, save for the slide side of things on each (need to get a new o-ring) and the damned pilot screw that I have to ez-out.  Thanks for the replies.