The 8800 is still a great movement, but there are two things to keep in mind about it: First, it doesn't have an independent hour hand, and second, it has "only" one mainspring (like 99% of mechanical movements, so don't consider this to be some massive shortcoming) and 55 hours of reserve rather than 60.
On the other hand, it's got a quickset date, which is very convenient if you rotate watches often and you don't use a watch winder. It can take a while to rotate the hour hand to move 15 days backwards or forwards.
The following is from my review of the new Seamaster Diver 300, which had the 8800 in it. Here's the movement section, which might be helpful.
And finally we arrive at my favorite section, the movement, which turned out to be surprisingly interesting. You, would, of course, anticipate that Omega would use their 8900 movement found in some other Seamasters like the Aqua Terra, as is only natural. But then you, like me, would be wrong, because what weíre looking at is not an 8900, but an 8800.
For instance, if we look closely, we can find only a single barrel for the mainspring, compared to the two barrels found in the 8900. Iíve highlighted it in green for your convenience. This means that the 8800 has a 55 hour power reserve, compared to the 8900ís 60, but thatís a pretty trivial difference, especially when you remember that 55 hours is still a solid 15 more than the vast majority of watches on the market today.
Other elements remain the same, however, like the co-axial escapement and free sprung balance wheel with silicon hairspring. The 8800 is capable of withstanding nearly any magnetic field you could throw at it, and like other Master Co-Axial Omegas, is unique in that it can provide that resistance while maintaining a display back. Itís a very elegant solution to the problem of magnetism. Where most companies try to quarantine their movements from magnets, Omega simply immunizes them at birth.
Likewise, the rather beautiful bridge remains, in theory making the movement a bit more robust than competing designs.
If itís so similar, but with a slightly smaller power reserve, you might be asking why bother using it instead of an 8900? Thatís because itís a substantially more compact movement than the 8900, but perhaps more precisely, because the 8800ís dimensions are pretty close to the old 2500 that it replaces.
The 8800 is just as beautiful as the 8900, being one of the prettiest mass-produced movements on the market, but it does have a couple of other small differences. For one thing, in the 8900, there is no quickset date, which means you have to rotate the hour hand around the dial to change the date. In the 8800, this is much easier, because you can set the date directly from the crown. Conversely, you give up the independent hour hand, making this a bit less travel friendly. Six of one, a half dozen of the other, itís just contingent on which feature youíd prefer to have. For most users, these will be the most important differences between the 8800 and 8900 because I donít expect there to be any appreciable difference in performance.