does 1+2 always equal 3

No. Personally, I would probably stay away from MTH's track unless I was desperate. Too many problems with their track and switches. 

"sjc" - thank you - what would you suggest

Gargraves or tubular with Ross switches.

Unfortunately there is no perfect track system that works with every train. I think they are all good track systems and can all perform well. However, one man's nightmare track can be the next man's dream track. And the manufacturer's own track doesn't necessarily mean their trains will run better on it. It might, but then again it might not?   

 

I would go and look at some different track systems (hopefully you have a train store you can go to) and make your selection on what you like, think is good quality and will look good on your layout. Buy a circle of track and a few straights and try it out. If you like it you are set, just add more. If not you can sell it and try something else. I don't think you will, but if you do have to sell it I don't think you will lose much on track that is still in like new condition.

 

While complaints are definitely worthy of consideration, I think they make up a small percentage of all the equipment that is sold and in use out there. My guess would be we have a much better chance of getting a good one of whatever it is than getting a bad one. And the manufacturers do try to correct the problems when either we or they have them. 

I run MTH and Gargraves..as long as you test it as you put the track down it really will not be an issue.  Don't attempt to make the track do things it cannot..forcing a piece to fit may seem OK, but not if it causes derailments.

i use a Truck off of a car that had its knuckle broken and i run it over the track with my hand on it..allows me to "feel" the track..also I use three cars to test ..2 long passenger cars with an MTH depressed center flat car in the middle..pushing back and forth numerous times..the goal is ZERO derailments in testing..smooth transitions, no jolting from track connections...I recommend you be in the mood to do the work..do not force yourself to do it..its supposed to be fun..and relaxing..I work when the mood hits me..5 PM or 2 AM...Afetr all I RUN THIS RAILROAD...

and I have a budget..so i buy used when I can...

well, I know an engineer that once reported that bkW = bhp and for some reason in the same email mistakenly effectively stated that ekW = bkW....

His manager called him and engineer's engineer and well, lets just leave it at that this guy might tell you that 1 + 2 = 15...