Which products are worth the modelmakers premium and which are not?
There are so many specialized products at mind blowing
prices, I'm looking for alternatives.
I'm no expert but I wonder. Is Tamiya CA really better than
Super Glue? Is Micro Crystal Glue better than Elmers?
Are all the expensive weathering formulas available really better than a simple wash or pastels or oils?
Do you have any bargain favorites?

I used CA glue exclusively, for many years. I recently tried out some different glues(even including Academy cement). Tamiya is the best I have found. Model Master glue is great for tracks. Much better than Testor's glue. As far as glue for clear parts go, I would stick with Elmer's. You shouldn't need an extremely strong bond.
You should implement pigments, washes(this is what you use oil paints for) and filters. Test out some of the different brands of pigments, to get a feel for what you like.

I bought chalk pastels at a local craft store. Both earth tone and the regular art colors, and ground them for pigment powders. I have also used clay and soil from the garden, rust and other natural (and free) materials for weathering, and they have worked fine for my tastes. Windsor and Newton oils have worked for my washes and oil dot filters.

I use and prefer the Tamiya extra thin cement for plastic. I also use odorless CA glue for etch and resin parts, and Gorilla Glue CA if the part will be put under any stress as it has some elasticity to it.

My opinion, but excel blades are better, and cheaper, than X-acto.

I bought two bottle of AK Interactive enamels, one a filter, an the other a wash. Using a cheap art caulk set of earth tones purchased from Michaels I made my own pigments by running them over 320 grit sandpaper. Then mixed my own washes and filters with plan old Orderless Mineral Spirits to the same consistency as the AK washes/filters. Took a little time testing, but the end results are exactly the same. I now have a life time supply of pigments, washes, and filters for next to nothing compared to the $9 per bottle I paid at my LHS.
Joel

Very subjective question. Many swear by a product, others hate it. Depends on so many things as well; availability, preferred techniques, skill level, experience, etc.
I have tried many products in the last 10 years, based on recommendations and results. Some have an immediate "WOW" effect, others are a total waste of money. I have used cheap products bought locally that are similar to very expensive versions, with equal or even better results.
The best way is to buy a sample of items that you find interesting, are curious about and/or based on recommendations. Some will work, some won´t. But experience is gained with each experiemnt. I have even found out that items I bought and didn´t like previously have worked later (and even vice versa).
Regarding cements/glues, I dont think there is one perfect cement/glue for all jobs. I use Tamiya thin for the most, but as Matt says, Model Master cement is perfect for indy plastic tracks. For assembling figures where you want a strong bond and a little melt to fill in any gaps, I use Humbrol Liquid Polly. For super glue I use mostly Loctite thin or gel depending on what is being glued. For diorama work I use a lot of woodwroking glue/PVC glue and hot glue. Experience and experimenting has shown what works best in whatever situation. And just because they work for me does not mean that you will automatically prefer them.

Yes and no. Again it depends on your own taste, experience and economic situation. Lost count on how many times over the years that modellers have asked how much to thin washes, etc. Now you have a chance to use a wash that is formulated by people who have a proven track record using such items.
I bought dome of the AK washes to try, eventhough I am quite comfortable with washes and filters ... but I wanted to have that experience. Probably wont buy any more as I can mix my own, but I have an undertsnding of what could be considered a norm or standard.
Another reason these items are popular is because they are convienience products. Many are prepared to pay a little extra to have a perfect wash at hand when needed, and are glad to skip the extra work.
It all comes down to what you want, prefer, can afford, etc. Only you can decide if they offer more than what can be done on a budget, but I believe its worth sampling and experimenting before deciding on whats best. Skill and experience may also be a major factor on what you decide works for you. What you are happy with today does not necessarily mean you will happy with next year or in a few years time. These products have a long shelf-life and even if you do not use them so much today, they could be regular items tomorrow. But you wont know if you dont try.