Especially if you can get it discounted! All the best. But if realism is important, and you love Swiss content (unique locos, different signalling and the wonderful scenery), then the SBB1 is certainly worth serious consideration. That's the best low down I can give on the Swiss route. Fictional but excellent, and significantly cheaper (especially if you grab it through JT's monthly newsletter discounts). But if you're not worried about that,and you haven't got it already you might want to look at the Three Country Corner route.
It also depends on how bothered you are about the route being real-life or fictional. Personally I'd rather have an atmospheric scenic and enjoyable route, over a graphically amazing dull to drive offering (we have plenty of those in the game!). The SBB1 whilst it may not be as slick graphically as new routes (such as Mannheim-Karlsruhe) in my opinion, they're perfectly adequate to make the route work well. If you have the Berlin-Wittenberg route you will have an idea of the high quality routes that Aerosoft + partners can produce.
It's simply a fun route to drive, with some great rolling stock to play with (again very authentic for Switzerland, a lot of effort in particular went into developing the SBB re 4/4 locos). They've used the genuine Swiss signalling system (which I believe was a real pain for the creators to develop) together with the unique signage for the tracks to go along with the signalling system. The SBB1 is the only real-life route we have for Switzerland, and they've picked a stunning part of the country to drive through. So all in, I think this is why they will always be classic loved routes for the game.
The perhaps slightly dated graphics are a complete non issue for me, because the overall driving experience, which is a lot of fun, outweighs any graphical limitations (which personally I feel are relatively small). I like the two mentioned German routes because they are atmospheric, the distant scenery is beautiful, the tracks are accurate, and they are reliable (largely bug free), with plenty to do (passenger, freight, shunting etc.). Well there might be a problem for you, if graphics are so important.