Hello Abc,
Knowing a little about watches and what not I will see if I can help you with your decision....
With regards to the Aquaterra and the various sizes, I believe you are quoting the old sizes as Omega has recently updated their website to reflect the accurate sizes of their watches
www.omega.ch. The new larger size designation for the Aqua Terra is 42.2mm, Omega has for the past few years had the habit of understating the sizes of their cases.
I cannot stress enough before you decide that you visit a store and try both sizes on, personally I find the 42mm large size to be far too big and almost clownish looking and I am not a small guy, I also feel there is too much empty dial on the piece, plus if you compare the 38mm to the 42 you will see that due to the movement design the date wheel is more towards the center on the larger watch which looks awkward whereas proportionally it looks better on the 38mm. However if you are a really big guy, or love large watches then the 42mm might be for you, ironically most of the people whom I have seen with the 42mm model have very very skinny wrists, they are even going to offer a 49mm model of the railmaster in manual wind only.
When deciding about quartz or automatic there are a few issues one has to consider. First off quartz will generally be far more accurate (in terms of consistancy) and require alot less and less expensive maintence than an automatic chronometer, plus the cost of admission for a quartz is considerably less, however as you mentioned you might be interested in the 42mm I don't believe Omega offers this in a quartz model. Automatics on the other hand generally have a higher resale value, or higher demand on the secondary market as they are much more sought after, to me they are more interesting and personally I would take one in an instant over a quartz. Also the quartz pieces do not have display backs and what not, the quartz movements Omega uses are slightly modified ETA quartz modules which are the norm in the industry for pieces in that price range, however the automatic movement they use in the chronometer is a heavily modified ETA 2892 which features not only their signature Daniel's Co-Axial escapement which supposedly improves long term accuracy, but also a free sprung micro regulated balance...two very high end features on a watch of this price point. Figure about $300-500 every five years to service the co axial (they advertise 10 year intervals but I and others highly doubt it) vs about $150 for a service on the quartz and that will be whenever the battery dies, possibly less or more for either depending on the work they do.
Someone mentioned that watches only have a year warranty, while that was the case with regards to Omega and other higher end Swiss companies it is no longer true, a little while back due to European union regulations all Swiss watch companies changed their warranty policy on standard pieces to two years, the Co-Axial version of the aqua terra has a three year factory warranty as it is one of the perks Omega is marketing. With so many authorised dealers out there willing to sell for 35% off or more I see little reason to buy grey market from the net, if you like you can PM me and I can refer you to another site where there is a dealer in DC who can give a great discount and you get the factory warranty.
Some things to know about Omega and tha Aqua Terra....someone below stated they preferred the Railmaster model over that of the standard Aqua Terra, while the Railmaster is a nice watch..point for point I think your money is best spend on a standard model unless you really like the dial style of the Railmaster...the models are the same price only with the Railmaster you do not get a date function and you do not get applied hour markers nor an applied logo.
Things to know about Omega...Omega makes excellent watches at somewhat reasonable prices, they are a part of the Swatch group and utilize a shared service facility in lancaster PA which has been reported to perform lacklustre service, many choose to send their pieces back to Switzerland for repair rather then have Lancaster botch up their watch (Figure higher costs for shipping and what not for repairs), Swatch/Omega has just implemented a policy that prohibits sale of parts to independant watch repair shops...many others in the industry also do the same thing but it makes things difficult with Omega as they only have one US service center and it isn't that great, there are a few authorised independants but they supposedly aren't that good either. Their new F. Piguet based chrono has had numerous problem reports (model 3303) and many have been somewhat unhappy, but the model you are looking at is based off a tried and true design, early revisions of the 2892 co axial had oiling problems but they have since been sorted out. The Aqua Terra is a great looking watch, and if I liked the hands and dial better I might have one...
Omega is currently in a battle to move their products up market so if you want this watch I advise you buy soon as they plan on tightening the reins and not allowing heavy dealer discounts anymore, in fact more than a few dealers have been dropped in this process, luckily that one in DC I know of is still authorised and plans to stay that way....don't know if they will still do the standard 35% off but I think they will still do 30% which is very good.
Check out
www.timezone.com and
www.chronocentric.com for alot of good Omega advice.....
Personally I am a Rolex fanatic, I have been involved in the watch communtiy for the past four years as an enthusiast/mild collector....while I enjoy Rolex more I also respect the Omega of old, when it was its own company and the leader of the pack...alot of their new pieces are nice but the companies policies and marketing really turn me off (too many celeb endorsements, botique shops, poor service)....
Other watches to consider are Tudor, Tissot and Oris for a little less money than the Omega....
Good luck and if you need any info feel free to PM me.