Quote #1 has 3/4" insulated glass and 4-9/16" jambs (2x4 framed wall)

Quote #2 has 1" insulated glass (same make-up as #1 just different overall thickness) and 6-9/16" jambs (2x6 framed wall)

#2 should probably be a little more maybe $150 or so.

Thanks for the information. A few more questions:
1- Will the soundproofing performance be better with one over the other?
2- There is a difference in the way the two pieces of glass are quoted--Quote 1 lists #ANNEALED 1PC 3/16" & 1PC 1/4" LoE272 w/ ARGON, whereas Quote 2 lists # 3/16" LoE w/argon & 1/4" clear. Are these two the same?
3- Why the difference in the jamb when it is the same house? If we were to install the 4 and house should have the 6, what effect would that have on the installation (or the reverse--installing a 6 when it should have been a 4)?
I know this is elementary to you guys, but I am really confused. Thanks!

The second quote says Bay Picture...The different jamb depth might have been an input error from who did the quote.

FT, I think the "bay" in bay picture meant (1) bay or lite. Not bay window, if that's what your thinking. What is you construction 2x4 (4-916" basically or 2x6 (6-9/16")? If 2x6 and they bought the units as 4-9/16" they would need to field apply an extension jamb to bring the unit out flush with the interior wall. 6-9/16" would have the extension made in 1 piece from the factory. Glass is the same with the exception of the 1" having a larger air space, which would probably give you a skosh better sound transmission (not noticeable more than likely).

The reference to bay in the quote is that this is the center window in a bay window unit. There are two casement windows that open adjacent to the picture unit.

The reference to bay in the quote is that this is the center window in a bay window unit. There are two casement windows that open adjacent to the picture unit.

OK, I stand corrected but if they are stand alone units the only differences are still as I mentioned